; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py ; RUN: llc -mtriple=x86_64-linux-gnu %s -o - -jump-table-density=40 -switch-peel-threshold=101 -verify-machineinstrs | FileCheck %s ; RUN: llc -mtriple=x86_64-linux-gnu %s -o - -O0 -jump-table-density=40 -verify-machineinstrs | FileCheck --check-prefix=NOOPT %s declare void @g(i32) ; Should be lowered as a jump table, both with and without optimization. define void @basic(i32 %x) { ; CHECK-LABEL: basic: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: decl %edi ; CHECK-NEXT: cmpl $4, %edi ; CHECK-NEXT: ja .LBB0_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: jmpq *.LJTI0_0(,%rdi,8) ; CHECK-NEXT: .LBB0_3: # %bb2 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB0_4: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB0_2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: basic: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, %eax ; NOOPT-NEXT: decl %eax ; NOOPT-NEXT: movl %eax, %ecx ; NOOPT-NEXT: movq %rcx, (%rsp) # 8-byte Spill ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: ja .LBB0_4 ; NOOPT-NEXT: # %bb.5: # %entry ; NOOPT-NEXT: movq (%rsp), %rax # 8-byte Reload ; NOOPT-NEXT: movq .LJTI0_0(,%rax,8), %rax ; NOOPT-NEXT: jmpq *%rax ; NOOPT-NEXT: .LBB0_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB0_4 ; NOOPT-NEXT: .LBB0_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB0_4 ; NOOPT-NEXT: .LBB0_3: # %bb2 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB0_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 3, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 5, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 1) br label %return return: ret void } ; Should never be lowered as a jump table because of the attribute define void @basic_nojumptable(i32 %x) "no-jump-tables"="true" { ; CHECK-LABEL: basic_nojumptable: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: jg .LBB1_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: cmpl $1, %edi ; CHECK-NEXT: je .LBB1_7 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: jne .LBB1_6 ; CHECK-NEXT: # %bb.3: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB1_4: # %entry ; CHECK-NEXT: cmpl $4, %edi ; CHECK-NEXT: je .LBB1_7 ; CHECK-NEXT: # %bb.5: # %entry ; CHECK-NEXT: cmpl $5, %edi ; CHECK-NEXT: jne .LBB1_6 ; CHECK-NEXT: .LBB1_7: # %bb2 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB1_6: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: basic_nojumptable: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $1, %edi ; NOOPT-NEXT: je .LBB1_2 ; NOOPT-NEXT: jmp .LBB1_5 ; NOOPT-NEXT: .LBB1_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB1_1 ; NOOPT-NEXT: jmp .LBB1_6 ; NOOPT-NEXT: .LBB1_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: je .LBB1_2 ; NOOPT-NEXT: jmp .LBB1_7 ; NOOPT-NEXT: .LBB1_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $5, %eax ; NOOPT-NEXT: je .LBB1_3 ; NOOPT-NEXT: jmp .LBB1_4 ; NOOPT-NEXT: .LBB1_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB1_4 ; NOOPT-NEXT: .LBB1_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB1_4 ; NOOPT-NEXT: .LBB1_3: # %bb2 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB1_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 3, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 5, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 1) br label %return return: ret void } ; Should be lowered as a jump table because of the attribute define void @basic_nojumptable_false(i32 %x) "no-jump-tables"="false" { ; CHECK-LABEL: basic_nojumptable_false: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: decl %edi ; CHECK-NEXT: cmpl $4, %edi ; CHECK-NEXT: ja .LBB2_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: jmpq *.LJTI2_0(,%rdi,8) ; CHECK-NEXT: .LBB2_3: # %bb2 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB2_4: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB2_2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: basic_nojumptable_false: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, %eax ; NOOPT-NEXT: decl %eax ; NOOPT-NEXT: movl %eax, %ecx ; NOOPT-NEXT: movq %rcx, (%rsp) # 8-byte Spill ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: ja .LBB2_4 ; NOOPT-NEXT: # %bb.5: # %entry ; NOOPT-NEXT: movq (%rsp), %rax # 8-byte Reload ; NOOPT-NEXT: movq .LJTI2_0(,%rax,8), %rax ; NOOPT-NEXT: jmpq *%rax ; NOOPT-NEXT: .LBB2_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB2_4 ; NOOPT-NEXT: .LBB2_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB2_4 ; NOOPT-NEXT: .LBB2_3: # %bb2 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB2_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 3, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 5, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 1) br label %return return: ret void } ; Should be lowered to two range checks. ; We do this even at -O0, because it's cheap and makes codegen faster. define void @simple_ranges(i32 %x) { ; CHECK-LABEL: simple_ranges: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: leal -100(%rdi), %eax ; CHECK-NEXT: cmpl $4, %eax ; CHECK-NEXT: jb .LBB3_3 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: ja .LBB3_4 ; CHECK-NEXT: # %bb.2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB3_3: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB3_4: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: simple_ranges: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $4, %edi ; NOOPT-NEXT: jb .LBB3_1 ; NOOPT-NEXT: jmp .LBB3_4 ; NOOPT-NEXT: .LBB3_4: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: addl $-100, %eax ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: jb .LBB3_2 ; NOOPT-NEXT: jmp .LBB3_3 ; NOOPT-NEXT: .LBB3_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB3_3 ; NOOPT-NEXT: .LBB3_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB3_3: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 1, label %bb0 i32 2, label %bb0 i32 3, label %bb0 i32 100, label %bb1 i32 101, label %bb1 i32 102, label %bb1 i32 103, label %bb1 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return return: ret void } ; Cases 0-5 could be lowered with two bit tests, ; but with 6-8, the whole switch is suitable for a jump table. define void @jt_is_better(i32 %x) { ; CHECK-LABEL: jt_is_better: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $8, %edi ; CHECK-NEXT: ja .LBB4_7 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: jmpq *.LJTI4_0(,%rax,8) ; CHECK-NEXT: .LBB4_2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB4_3: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB4_7: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB4_4: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB4_5: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB4_6: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: jt_is_better: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, %eax ; NOOPT-NEXT: # kill: def $rax killed $eax ; NOOPT-NEXT: movq %rax, (%rsp) # 8-byte Spill ; NOOPT-NEXT: subl $8, %edi ; NOOPT-NEXT: ja .LBB4_6 ; NOOPT-NEXT: # %bb.7: # %entry ; NOOPT-NEXT: movq (%rsp), %rax # 8-byte Reload ; NOOPT-NEXT: movq .LJTI4_0(,%rax,8), %rax ; NOOPT-NEXT: jmpq *%rax ; NOOPT-NEXT: .LBB4_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB4_6 ; NOOPT-NEXT: .LBB4_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB4_6 ; NOOPT-NEXT: .LBB4_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB4_6 ; NOOPT-NEXT: .LBB4_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB4_6 ; NOOPT-NEXT: .LBB4_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB4_6: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 2, label %bb0 i32 4, label %bb0 i32 1, label %bb1 i32 3, label %bb1 i32 5, label %bb1 i32 6, label %bb2 i32 7, label %bb3 i32 8, label %bb4 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return return: ret void } ; This could be lowered as a jump table, but bit tests is more efficient. ; The bit test on 2,5,8 is unnecessary as all cases cover the rage [0, 8]. ; The range check guarantees that cases other than 0,3,6 and 1,4,7 must be ; in 2,5,8. define void @bt_is_better(i32 %x) { ; CHECK-LABEL: bt_is_better: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $8, %edi ; CHECK-NEXT: ja .LBB5_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movl $73, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jb .LBB5_5 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: movl $146, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB5_3 ; CHECK-NEXT: # %bb.6: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB5_5: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB5_3: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB5_4: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: bt_is_better: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB5_1 ; NOOPT-NEXT: jmp .LBB5_5 ; NOOPT-NEXT: .LBB5_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $1, %eax ; NOOPT-NEXT: je .LBB5_2 ; NOOPT-NEXT: jmp .LBB5_6 ; NOOPT-NEXT: .LBB5_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB5_3 ; NOOPT-NEXT: jmp .LBB5_7 ; NOOPT-NEXT: .LBB5_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB5_1 ; NOOPT-NEXT: jmp .LBB5_8 ; NOOPT-NEXT: .LBB5_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: je .LBB5_2 ; NOOPT-NEXT: jmp .LBB5_9 ; NOOPT-NEXT: .LBB5_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $5, %eax ; NOOPT-NEXT: je .LBB5_3 ; NOOPT-NEXT: jmp .LBB5_10 ; NOOPT-NEXT: .LBB5_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $6, %eax ; NOOPT-NEXT: je .LBB5_1 ; NOOPT-NEXT: jmp .LBB5_11 ; NOOPT-NEXT: .LBB5_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $7, %eax ; NOOPT-NEXT: je .LBB5_2 ; NOOPT-NEXT: jmp .LBB5_12 ; NOOPT-NEXT: .LBB5_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $8, %eax ; NOOPT-NEXT: je .LBB5_3 ; NOOPT-NEXT: jmp .LBB5_4 ; NOOPT-NEXT: .LBB5_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB5_4 ; NOOPT-NEXT: .LBB5_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB5_4 ; NOOPT-NEXT: .LBB5_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB5_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 3, label %bb0 i32 6, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 7, label %bb1 i32 2, label %bb2 i32 5, label %bb2 i32 8, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return return: ret void } ; This will also be lowered as bit test, but as the range [0,8] is not fully ; covered (5 missing), the default statement can be jumped to and we end up ; with one more branch. define void @bt_is_better2(i32 %x) { ; CHECK-LABEL: bt_is_better2: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $8, %edi ; CHECK-NEXT: ja .LBB6_7 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movl $73, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jb .LBB6_5 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: movl $146, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB6_3 ; CHECK-NEXT: # %bb.6: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB6_5: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB6_3: # %entry ; CHECK-NEXT: movl $260, %eax # imm = 0x104 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB6_7 ; CHECK-NEXT: # %bb.4: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB6_7: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: bt_is_better2: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB6_1 ; NOOPT-NEXT: jmp .LBB6_5 ; NOOPT-NEXT: .LBB6_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $1, %eax ; NOOPT-NEXT: je .LBB6_2 ; NOOPT-NEXT: jmp .LBB6_6 ; NOOPT-NEXT: .LBB6_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB6_3 ; NOOPT-NEXT: jmp .LBB6_7 ; NOOPT-NEXT: .LBB6_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB6_1 ; NOOPT-NEXT: jmp .LBB6_8 ; NOOPT-NEXT: .LBB6_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: je .LBB6_2 ; NOOPT-NEXT: jmp .LBB6_9 ; NOOPT-NEXT: .LBB6_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $6, %eax ; NOOPT-NEXT: je .LBB6_1 ; NOOPT-NEXT: jmp .LBB6_10 ; NOOPT-NEXT: .LBB6_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $7, %eax ; NOOPT-NEXT: je .LBB6_2 ; NOOPT-NEXT: jmp .LBB6_11 ; NOOPT-NEXT: .LBB6_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $8, %eax ; NOOPT-NEXT: je .LBB6_3 ; NOOPT-NEXT: jmp .LBB6_4 ; NOOPT-NEXT: .LBB6_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB6_4 ; NOOPT-NEXT: .LBB6_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB6_4 ; NOOPT-NEXT: .LBB6_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB6_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 3, label %bb0 i32 6, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 7, label %bb1 i32 2, label %bb2 i32 8, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return return: ret void } define void @bt_is_better3(i32 %x) { ; CHECK-LABEL: bt_is_better3: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $18, %edi ; CHECK-NEXT: ja .LBB7_7 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movl $74752, %eax # imm = 0x12400 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jb .LBB7_5 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: movl $149504, %eax # imm = 0x24800 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB7_3 ; CHECK-NEXT: # %bb.6: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB7_5: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB7_3: # %entry ; CHECK-NEXT: movl $266240, %eax # imm = 0x41000 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB7_7 ; CHECK-NEXT: # %bb.4: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB7_7: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: bt_is_better3: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $10, %edi ; NOOPT-NEXT: je .LBB7_1 ; NOOPT-NEXT: jmp .LBB7_5 ; NOOPT-NEXT: .LBB7_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $11, %eax ; NOOPT-NEXT: je .LBB7_2 ; NOOPT-NEXT: jmp .LBB7_6 ; NOOPT-NEXT: .LBB7_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $12, %eax ; NOOPT-NEXT: je .LBB7_3 ; NOOPT-NEXT: jmp .LBB7_7 ; NOOPT-NEXT: .LBB7_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $13, %eax ; NOOPT-NEXT: je .LBB7_1 ; NOOPT-NEXT: jmp .LBB7_8 ; NOOPT-NEXT: .LBB7_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $14, %eax ; NOOPT-NEXT: je .LBB7_2 ; NOOPT-NEXT: jmp .LBB7_9 ; NOOPT-NEXT: .LBB7_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $16, %eax ; NOOPT-NEXT: je .LBB7_1 ; NOOPT-NEXT: jmp .LBB7_10 ; NOOPT-NEXT: .LBB7_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $17, %eax ; NOOPT-NEXT: je .LBB7_2 ; NOOPT-NEXT: jmp .LBB7_11 ; NOOPT-NEXT: .LBB7_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $18, %eax ; NOOPT-NEXT: je .LBB7_3 ; NOOPT-NEXT: jmp .LBB7_4 ; NOOPT-NEXT: .LBB7_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB7_4 ; NOOPT-NEXT: .LBB7_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB7_4 ; NOOPT-NEXT: .LBB7_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB7_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 10, label %bb0 i32 13, label %bb0 i32 16, label %bb0 i32 11, label %bb1 i32 14, label %bb1 i32 17, label %bb1 i32 12, label %bb2 i32 18, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return return: ret void ; We don't have to subtract 10 from the case value to let the range become ; [0, 8], as each value in the range [10, 18] can be represented by bits in a ; word. Then we still need a branch to jump to the default statement for the ; range [0, 10). ; 74752 = 2^10 + 2^13 + 2^16 ; 149504 = 2^11 + 2^14 + 2^17 ; 266240 = 2^12 + 2^15 + 2^18 } ; Should pivot around 400 for two subtrees of equal size. define void @optimal_pivot1(i32 %x) { ; CHECK-LABEL: optimal_pivot1: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $399, %edi # imm = 0x18F ; CHECK-NEXT: jg .LBB8_5 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: cmpl $100, %edi ; CHECK-NEXT: je .LBB8_8 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: cmpl $200, %edi ; CHECK-NEXT: je .LBB8_9 ; CHECK-NEXT: # %bb.3: # %entry ; CHECK-NEXT: cmpl $300, %edi # imm = 0x12C ; CHECK-NEXT: je .LBB8_8 ; CHECK-NEXT: .LBB8_4: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB8_5: # %entry ; CHECK-NEXT: cmpl $400, %edi # imm = 0x190 ; CHECK-NEXT: je .LBB8_9 ; CHECK-NEXT: # %bb.6: # %entry ; CHECK-NEXT: cmpl $600, %edi # imm = 0x258 ; CHECK-NEXT: je .LBB8_9 ; CHECK-NEXT: # %bb.7: # %entry ; CHECK-NEXT: cmpl $500, %edi # imm = 0x1F4 ; CHECK-NEXT: jne .LBB8_4 ; CHECK-NEXT: .LBB8_8: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB8_9: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: optimal_pivot1: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $100, %edi ; NOOPT-NEXT: je .LBB8_1 ; NOOPT-NEXT: jmp .LBB8_4 ; NOOPT-NEXT: .LBB8_4: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $200, %eax ; NOOPT-NEXT: je .LBB8_2 ; NOOPT-NEXT: jmp .LBB8_5 ; NOOPT-NEXT: .LBB8_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $300, %eax # imm = 0x12C ; NOOPT-NEXT: je .LBB8_1 ; NOOPT-NEXT: jmp .LBB8_6 ; NOOPT-NEXT: .LBB8_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $400, %eax # imm = 0x190 ; NOOPT-NEXT: je .LBB8_2 ; NOOPT-NEXT: jmp .LBB8_7 ; NOOPT-NEXT: .LBB8_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $500, %eax # imm = 0x1F4 ; NOOPT-NEXT: je .LBB8_1 ; NOOPT-NEXT: jmp .LBB8_8 ; NOOPT-NEXT: .LBB8_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $600, %eax # imm = 0x258 ; NOOPT-NEXT: je .LBB8_2 ; NOOPT-NEXT: jmp .LBB8_3 ; NOOPT-NEXT: .LBB8_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB8_3 ; NOOPT-NEXT: .LBB8_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB8_3: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 100, label %bb0 i32 200, label %bb1 i32 300, label %bb0 i32 400, label %bb1 i32 500, label %bb0 i32 600, label %bb1 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return return: ret void } ; Should pivot around 300 for two subtrees with two jump tables each. define void @optimal_pivot2(i32 %x) { ; CHECK-LABEL: optimal_pivot2: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: cmpl $299, %edi # imm = 0x12B ; CHECK-NEXT: jg .LBB9_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: leal -100(%rdi), %eax ; CHECK-NEXT: cmpl $3, %eax ; CHECK-NEXT: jbe .LBB9_12 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: addl $-200, %edi ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: ja .LBB9_11 ; CHECK-NEXT: # %bb.3: # %entry ; CHECK-NEXT: jmpq *.LJTI9_1(,%rdi,8) ; CHECK-NEXT: .LBB9_4: # %entry ; CHECK-NEXT: leal -300(%rdi), %eax ; CHECK-NEXT: cmpl $3, %eax ; CHECK-NEXT: jbe .LBB9_13 ; CHECK-NEXT: # %bb.5: # %entry ; CHECK-NEXT: addl $-400, %edi # imm = 0xFE70 ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: ja .LBB9_11 ; CHECK-NEXT: # %bb.6: # %entry ; CHECK-NEXT: jmpq *.LJTI9_3(,%rdi,8) ; CHECK-NEXT: .LBB9_12: # %entry ; CHECK-NEXT: jmpq *.LJTI9_0(,%rax,8) ; CHECK-NEXT: .LBB9_13: # %entry ; CHECK-NEXT: jmpq *.LJTI9_2(,%rax,8) ; CHECK-NEXT: .LBB9_7: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB9_8: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB9_9: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB9_10: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB9_11: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: optimal_pivot2: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $100, %edi ; NOOPT-NEXT: je .LBB9_1 ; NOOPT-NEXT: jmp .LBB9_6 ; NOOPT-NEXT: .LBB9_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $101, %eax ; NOOPT-NEXT: je .LBB9_2 ; NOOPT-NEXT: jmp .LBB9_7 ; NOOPT-NEXT: .LBB9_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $102, %eax ; NOOPT-NEXT: je .LBB9_3 ; NOOPT-NEXT: jmp .LBB9_8 ; NOOPT-NEXT: .LBB9_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $103, %eax ; NOOPT-NEXT: je .LBB9_4 ; NOOPT-NEXT: jmp .LBB9_9 ; NOOPT-NEXT: .LBB9_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $200, %eax ; NOOPT-NEXT: je .LBB9_1 ; NOOPT-NEXT: jmp .LBB9_10 ; NOOPT-NEXT: .LBB9_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $201, %eax ; NOOPT-NEXT: je .LBB9_2 ; NOOPT-NEXT: jmp .LBB9_11 ; NOOPT-NEXT: .LBB9_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $202, %eax ; NOOPT-NEXT: je .LBB9_3 ; NOOPT-NEXT: jmp .LBB9_12 ; NOOPT-NEXT: .LBB9_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $203, %eax ; NOOPT-NEXT: je .LBB9_4 ; NOOPT-NEXT: jmp .LBB9_13 ; NOOPT-NEXT: .LBB9_13: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $300, %eax # imm = 0x12C ; NOOPT-NEXT: je .LBB9_1 ; NOOPT-NEXT: jmp .LBB9_14 ; NOOPT-NEXT: .LBB9_14: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $301, %eax # imm = 0x12D ; NOOPT-NEXT: je .LBB9_2 ; NOOPT-NEXT: jmp .LBB9_15 ; NOOPT-NEXT: .LBB9_15: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $302, %eax # imm = 0x12E ; NOOPT-NEXT: je .LBB9_3 ; NOOPT-NEXT: jmp .LBB9_16 ; NOOPT-NEXT: .LBB9_16: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $303, %eax # imm = 0x12F ; NOOPT-NEXT: je .LBB9_4 ; NOOPT-NEXT: jmp .LBB9_17 ; NOOPT-NEXT: .LBB9_17: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $400, %eax # imm = 0x190 ; NOOPT-NEXT: je .LBB9_1 ; NOOPT-NEXT: jmp .LBB9_18 ; NOOPT-NEXT: .LBB9_18: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $401, %eax # imm = 0x191 ; NOOPT-NEXT: je .LBB9_2 ; NOOPT-NEXT: jmp .LBB9_19 ; NOOPT-NEXT: .LBB9_19: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $402, %eax # imm = 0x192 ; NOOPT-NEXT: je .LBB9_3 ; NOOPT-NEXT: jmp .LBB9_20 ; NOOPT-NEXT: .LBB9_20: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $403, %eax # imm = 0x193 ; NOOPT-NEXT: je .LBB9_4 ; NOOPT-NEXT: jmp .LBB9_5 ; NOOPT-NEXT: .LBB9_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB9_5 ; NOOPT-NEXT: .LBB9_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB9_5 ; NOOPT-NEXT: .LBB9_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB9_5 ; NOOPT-NEXT: .LBB9_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB9_5: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 100, label %bb0 i32 101, label %bb1 i32 102, label %bb2 i32 103, label %bb3 i32 200, label %bb0 i32 201, label %bb1 i32 202, label %bb2 i32 203, label %bb3 i32 300, label %bb0 i32 301, label %bb1 i32 302, label %bb2 i32 303, label %bb3 i32 400, label %bb0 i32 401, label %bb1 i32 402, label %bb2 i32 403, label %bb3 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return return: ret void } ; Splitting in the largest gap (between 6 and 12) would yield suboptimal result. ; Expecting a jump table from 5 to 15. ; At -O0, we don't build jump tables for only parts of a switch. define void @optimal_jump_table1(i32 %x) { ; CHECK-LABEL: optimal_jump_table1: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: leal -5(%rdi), %eax ; CHECK-NEXT: cmpl $10, %eax ; CHECK-NEXT: ja .LBB10_1 ; CHECK-NEXT: # %bb.9: # %entry ; CHECK-NEXT: jmpq *.LJTI10_0(,%rax,8) ; CHECK-NEXT: .LBB10_3: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB10_1: # %entry ; CHECK-NEXT: testl %edi, %edi ; CHECK-NEXT: jne .LBB10_8 ; CHECK-NEXT: # %bb.2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB10_8: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB10_4: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB10_5: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB10_6: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB10_7: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: optimal_jump_table1: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB10_1 ; NOOPT-NEXT: jmp .LBB10_8 ; NOOPT-NEXT: .LBB10_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $5, %eax ; NOOPT-NEXT: je .LBB10_2 ; NOOPT-NEXT: jmp .LBB10_9 ; NOOPT-NEXT: .LBB10_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $6, %eax ; NOOPT-NEXT: je .LBB10_3 ; NOOPT-NEXT: jmp .LBB10_10 ; NOOPT-NEXT: .LBB10_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $12, %eax ; NOOPT-NEXT: je .LBB10_4 ; NOOPT-NEXT: jmp .LBB10_11 ; NOOPT-NEXT: .LBB10_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $13, %eax ; NOOPT-NEXT: je .LBB10_5 ; NOOPT-NEXT: jmp .LBB10_12 ; NOOPT-NEXT: .LBB10_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $15, %eax ; NOOPT-NEXT: je .LBB10_6 ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB10_7 ; NOOPT-NEXT: .LBB10_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB10_7: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 5, label %bb1 i32 6, label %bb2 i32 12, label %bb3 i32 13, label %bb4 i32 15, label %bb5 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return return: ret void } ; Partitioning the cases to the minimum number of dense sets is not good enough. ; This can be partitioned as {0,1,2,9},{14,15} or {0,1,2},{9,14,15}. The former ; should be preferred. Expecting a table from 0-9. define void @optimal_jump_table2(i32 %x) { ; CHECK-LABEL: optimal_jump_table2: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $9, %edi ; CHECK-NEXT: ja .LBB11_1 ; CHECK-NEXT: # %bb.10: # %entry ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: jmpq *.LJTI11_0(,%rax,8) ; CHECK-NEXT: .LBB11_4: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB11_1: # %entry ; CHECK-NEXT: cmpl $14, %edi ; CHECK-NEXT: je .LBB11_8 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: cmpl $15, %edi ; CHECK-NEXT: jne .LBB11_9 ; CHECK-NEXT: # %bb.3: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB11_9: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB11_5: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB11_6: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB11_7: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB11_8: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: optimal_jump_table2: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB11_1 ; NOOPT-NEXT: jmp .LBB11_8 ; NOOPT-NEXT: .LBB11_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $1, %eax ; NOOPT-NEXT: je .LBB11_2 ; NOOPT-NEXT: jmp .LBB11_9 ; NOOPT-NEXT: .LBB11_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB11_3 ; NOOPT-NEXT: jmp .LBB11_10 ; NOOPT-NEXT: .LBB11_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $9, %eax ; NOOPT-NEXT: je .LBB11_4 ; NOOPT-NEXT: jmp .LBB11_11 ; NOOPT-NEXT: .LBB11_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $14, %eax ; NOOPT-NEXT: je .LBB11_5 ; NOOPT-NEXT: jmp .LBB11_12 ; NOOPT-NEXT: .LBB11_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $15, %eax ; NOOPT-NEXT: je .LBB11_6 ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB11_7 ; NOOPT-NEXT: .LBB11_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB11_7: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 1, label %bb1 i32 2, label %bb2 i32 9, label %bb3 i32 14, label %bb4 i32 15, label %bb5 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return return: ret void } ; Splitting to maximize left-right density sum and gap size would split this ; between 3 and 10, and then between 20 and 25. It's better to build a table ; from 1-20. define void @optimal_jump_table3(i32 %x) { ; CHECK-LABEL: optimal_jump_table3: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: leal -1(%rdi), %eax ; CHECK-NEXT: cmpl $19, %eax ; CHECK-NEXT: ja .LBB12_1 ; CHECK-NEXT: # %bb.3: # %entry ; CHECK-NEXT: jmpq *.LJTI12_0(,%rax,8) ; CHECK-NEXT: .LBB12_4: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB12_5: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB12_6: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB12_7: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB12_1: # %entry ; CHECK-NEXT: cmpl $25, %edi ; CHECK-NEXT: jne .LBB12_8 ; CHECK-NEXT: # %bb.2: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB12_8: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: optimal_jump_table3: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $1, %edi ; NOOPT-NEXT: je .LBB12_1 ; NOOPT-NEXT: jmp .LBB12_7 ; NOOPT-NEXT: .LBB12_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB12_2 ; NOOPT-NEXT: jmp .LBB12_8 ; NOOPT-NEXT: .LBB12_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB12_3 ; NOOPT-NEXT: jmp .LBB12_9 ; NOOPT-NEXT: .LBB12_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $10, %eax ; NOOPT-NEXT: je .LBB12_4 ; NOOPT-NEXT: jmp .LBB12_10 ; NOOPT-NEXT: .LBB12_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $13, %eax ; NOOPT-NEXT: je .LBB12_1 ; NOOPT-NEXT: jmp .LBB12_11 ; NOOPT-NEXT: .LBB12_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $14, %eax ; NOOPT-NEXT: je .LBB12_2 ; NOOPT-NEXT: jmp .LBB12_12 ; NOOPT-NEXT: .LBB12_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $15, %eax ; NOOPT-NEXT: je .LBB12_3 ; NOOPT-NEXT: jmp .LBB12_13 ; NOOPT-NEXT: .LBB12_13: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $20, %eax ; NOOPT-NEXT: je .LBB12_4 ; NOOPT-NEXT: jmp .LBB12_14 ; NOOPT-NEXT: .LBB12_14: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $25, %eax ; NOOPT-NEXT: je .LBB12_5 ; NOOPT-NEXT: jmp .LBB12_6 ; NOOPT-NEXT: .LBB12_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB12_6 ; NOOPT-NEXT: .LBB12_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB12_6 ; NOOPT-NEXT: .LBB12_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB12_6 ; NOOPT-NEXT: .LBB12_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB12_6 ; NOOPT-NEXT: .LBB12_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB12_6: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 1, label %bb0 i32 2, label %bb1 i32 3, label %bb2 i32 10, label %bb3 i32 13, label %bb0 i32 14, label %bb1 i32 15, label %bb2 i32 20, label %bb3 i32 25, label %bb4 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return return: ret void } %struct.S = type { ptr, i32 } ; This will be lowered to a comparison with 4 and then bit tests. Make sure ; that the phi node in %header gets a value from the comparison block. define void @phi_node_trouble(ptr %s) { ; CHECK-LABEL: phi_node_trouble: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: .p2align 4, 0x90 ; CHECK-NEXT: .LBB13_1: # %header ; CHECK-NEXT: # =>This Inner Loop Header: Depth=1 ; CHECK-NEXT: testq %rdi, %rdi ; CHECK-NEXT: je .LBB13_5 ; CHECK-NEXT: # %bb.2: # %loop ; CHECK-NEXT: # in Loop: Header=BB13_1 Depth=1 ; CHECK-NEXT: movq (%rdi), %rdi ; CHECK-NEXT: movl 8(%rdi), %eax ; CHECK-NEXT: cmpl $4, %eax ; CHECK-NEXT: je .LBB13_1 ; CHECK-NEXT: # %bb.3: # %loop ; CHECK-NEXT: addl $-25, %eax ; CHECK-NEXT: cmpl $44, %eax ; CHECK-NEXT: ja .LBB13_5 ; CHECK-NEXT: # %bb.4: # %loop ; CHECK-NEXT: movabsq $17592186046465, %rcx # imm = 0x100000000801 ; CHECK-NEXT: btq %rax, %rcx ; CHECK-NEXT: .LBB13_5: # %exit2 ; CHECK-NEXT: retq ; ; NOOPT-LABEL: phi_node_trouble: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: movq %rdi, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill ; NOOPT-NEXT: jmp .LBB13_1 ; NOOPT-NEXT: .LBB13_1: # %header ; NOOPT-NEXT: # =>This Inner Loop Header: Depth=1 ; NOOPT-NEXT: movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload ; NOOPT-NEXT: movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill ; NOOPT-NEXT: cmpq $0, %rax ; NOOPT-NEXT: je .LBB13_3 ; NOOPT-NEXT: # %bb.2: # %loop ; NOOPT-NEXT: # in Loop: Header=BB13_1 Depth=1 ; NOOPT-NEXT: movq {{[-0-9]+}}(%r{{[sb]}}p), %rax # 8-byte Reload ; NOOPT-NEXT: movq (%rax), %rax ; NOOPT-NEXT: movl 8(%rax), %ecx ; NOOPT-NEXT: movl %ecx, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $4, %ecx ; NOOPT-NEXT: movq %rax, {{[-0-9]+}}(%r{{[sb]}}p) # 8-byte Spill ; NOOPT-NEXT: je .LBB13_1 ; NOOPT-NEXT: jmp .LBB13_5 ; NOOPT-NEXT: .LBB13_5: # %loop ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $25, %eax ; NOOPT-NEXT: je .LBB13_4 ; NOOPT-NEXT: jmp .LBB13_6 ; NOOPT-NEXT: .LBB13_6: # %loop ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $36, %eax ; NOOPT-NEXT: je .LBB13_4 ; NOOPT-NEXT: jmp .LBB13_7 ; NOOPT-NEXT: .LBB13_7: # %loop ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $69, %eax ; NOOPT-NEXT: je .LBB13_4 ; NOOPT-NEXT: jmp .LBB13_3 ; NOOPT-NEXT: .LBB13_3: # %exit ; NOOPT-NEXT: retq ; NOOPT-NEXT: .LBB13_4: # %exit2 ; NOOPT-NEXT: retq entry: br label %header header: %ptr = phi ptr [ %s, %entry ], [ %next, %loop ] %bool = icmp eq ptr %ptr, null br i1 %bool, label %exit, label %loop loop: %next = load ptr, ptr %ptr %xptr = getelementptr inbounds %struct.S, ptr %next, i64 0, i32 1 %x = load i32, ptr %xptr switch i32 %x, label %exit [ i32 4, label %header i32 36, label %exit2 i32 69, label %exit2 i32 25, label %exit2 ] exit: ret void exit2: ret void } ; Branch directly to the default. ; (In optimized builds the switch is removed earlier.) define void @default_only(i32 %x) { ; CHECK-LABEL: default_only: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: retq ; ; NOOPT-LABEL: default_only: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: jmp .LBB14_2 ; NOOPT-NEXT: .LBB14_1: # %return ; NOOPT-NEXT: retq ; NOOPT-NEXT: .LBB14_2: # %sw ; NOOPT-NEXT: jmp .LBB14_1 entry: br label %sw return: ret void sw: switch i32 %x, label %return [ ] } ; Don't infloop on jump tables where the upper bound is the max value of the ; input type (in this case 127). define void @int_max_table_cluster(i8 %x) { ; CHECK-LABEL: int_max_table_cluster: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: cmpb $-9, %dil ; CHECK-NEXT: ja .LBB15_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movzbl %dil, %eax ; CHECK-NEXT: jmpq *.LJTI15_0(,%rax,8) ; CHECK-NEXT: .LBB15_2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB15_3: # %bb3 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB15_4: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: int_max_table_cluster: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movb %dil, %al ; NOOPT-NEXT: addb $64, %al ; NOOPT-NEXT: movzbl %al, %ecx ; NOOPT-NEXT: # kill: def $rcx killed $ecx ; NOOPT-NEXT: movq %rcx, (%rsp) # 8-byte Spill ; NOOPT-NEXT: subb $-65, %al ; NOOPT-NEXT: ja .LBB15_5 ; NOOPT-NEXT: # %bb.6: # %entry ; NOOPT-NEXT: movq (%rsp), %rax # 8-byte Reload ; NOOPT-NEXT: movq .LJTI15_0(,%rax,8), %rax ; NOOPT-NEXT: jmpq *%rax ; NOOPT-NEXT: .LBB15_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB15_5 ; NOOPT-NEXT: .LBB15_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB15_5 ; NOOPT-NEXT: .LBB15_3: # %bb2 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB15_5 ; NOOPT-NEXT: .LBB15_4: # %bb3 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB15_5: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i8 %x, label %return [ i8 0, label %bb0 i8 1, label %bb0 i8 2, label %bb0 i8 3, label %bb0 i8 4, label %bb0 i8 5, label %bb0 i8 6, label %bb0 i8 7, label %bb0 i8 8, label %bb0 i8 9, label %bb0 i8 10, label %bb0 i8 11, label %bb0 i8 12, label %bb0 i8 13, label %bb0 i8 14, label %bb0 i8 15, label %bb0 i8 16, label %bb0 i8 17, label %bb0 i8 18, label %bb0 i8 19, label %bb0 i8 20, label %bb0 i8 21, label %bb0 i8 22, label %bb0 i8 23, label %bb0 i8 24, label %bb0 i8 25, label %bb0 i8 26, label %bb0 i8 27, label %bb0 i8 28, label %bb0 i8 29, label %bb0 i8 30, label %bb0 i8 31, label %bb0 i8 32, label %bb0 i8 33, label %bb0 i8 34, label %bb0 i8 35, label %bb0 i8 36, label %bb0 i8 37, label %bb0 i8 38, label %bb0 i8 39, label %bb0 i8 40, label %bb0 i8 41, label %bb0 i8 42, label %bb0 i8 43, label %bb0 i8 44, label %bb0 i8 45, label %bb0 i8 46, label %bb0 i8 47, label %bb0 i8 48, label %bb0 i8 49, label %bb0 i8 50, label %bb0 i8 51, label %bb0 i8 52, label %bb0 i8 53, label %bb0 i8 54, label %bb0 i8 55, label %bb0 i8 56, label %bb0 i8 57, label %bb0 i8 58, label %bb0 i8 59, label %bb0 i8 60, label %bb0 i8 61, label %bb0 i8 62, label %bb0 i8 63, label %bb0 i8 64, label %bb0 i8 65, label %bb0 i8 66, label %bb0 i8 67, label %bb0 i8 68, label %bb0 i8 69, label %bb0 i8 70, label %bb0 i8 71, label %bb0 i8 72, label %bb0 i8 73, label %bb0 i8 74, label %bb0 i8 75, label %bb0 i8 76, label %bb0 i8 77, label %bb0 i8 78, label %bb0 i8 79, label %bb0 i8 80, label %bb0 i8 81, label %bb0 i8 82, label %bb0 i8 83, label %bb0 i8 84, label %bb0 i8 85, label %bb0 i8 86, label %bb0 i8 87, label %bb0 i8 88, label %bb0 i8 89, label %bb0 i8 90, label %bb0 i8 91, label %bb0 i8 92, label %bb0 i8 93, label %bb0 i8 94, label %bb0 i8 95, label %bb0 i8 96, label %bb0 i8 97, label %bb0 i8 98, label %bb0 i8 99, label %bb0 i8 100, label %bb0 i8 101, label %bb0 i8 102, label %bb0 i8 103, label %bb0 i8 104, label %bb0 i8 105, label %bb0 i8 106, label %bb0 i8 107, label %bb0 i8 108, label %bb0 i8 109, label %bb0 i8 110, label %bb0 i8 111, label %bb0 i8 112, label %bb0 i8 113, label %bb0 i8 114, label %bb0 i8 115, label %bb0 i8 116, label %bb0 i8 117, label %bb0 i8 118, label %bb0 i8 119, label %bb0 i8 120, label %bb0 i8 121, label %bb0 i8 122, label %bb0 i8 123, label %bb0 i8 124, label %bb0 i8 125, label %bb0 i8 126, label %bb0 i8 127, label %bb0 i8 -64, label %bb1 i8 -63, label %bb1 i8 -62, label %bb1 i8 -61, label %bb1 i8 -60, label %bb1 i8 -59, label %bb1 i8 -58, label %bb1 i8 -57, label %bb1 i8 -56, label %bb1 i8 -55, label %bb1 i8 -54, label %bb1 i8 -53, label %bb1 i8 -52, label %bb1 i8 -51, label %bb1 i8 -50, label %bb1 i8 -49, label %bb1 i8 -48, label %bb1 i8 -47, label %bb1 i8 -46, label %bb1 i8 -45, label %bb1 i8 -44, label %bb1 i8 -43, label %bb1 i8 -42, label %bb1 i8 -41, label %bb1 i8 -40, label %bb1 i8 -39, label %bb1 i8 -38, label %bb1 i8 -37, label %bb1 i8 -36, label %bb1 i8 -35, label %bb1 i8 -34, label %bb1 i8 -33, label %bb1 i8 -32, label %bb2 i8 -31, label %bb2 i8 -30, label %bb2 i8 -29, label %bb2 i8 -28, label %bb2 i8 -27, label %bb2 i8 -26, label %bb2 i8 -25, label %bb2 i8 -24, label %bb2 i8 -23, label %bb2 i8 -22, label %bb2 i8 -21, label %bb2 i8 -20, label %bb2 i8 -19, label %bb2 i8 -18, label %bb2 i8 -17, label %bb2 i8 -16, label %bb3 i8 -15, label %bb3 i8 -14, label %bb3 i8 -13, label %bb3 i8 -12, label %bb3 i8 -11, label %bb3 i8 -10, label %bb3 i8 -9, label %bb3 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 1) br label %return bb3: tail call void @g(i32 1) br label %return return: ret void } ; Cases 1,4,7 have a very large branch weight (which shouldn't overflow), so ; their bit test should come first. 0,3,6 and 2,5,8,9 both have a weight of 20, ; but the latter set has more cases, so should be tested for earlier. The bit ; test on 0,3,6 is unnecessary as all cases cover the range [0, 9]. The range ; check guarantees that cases other than 1,4,7 and 2,5,8,9 must be in 0,3,6. define void @bt_order_by_weight(i32 %x) { ; CHECK-LABEL: bt_order_by_weight: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $9, %edi ; CHECK-NEXT: ja .LBB16_6 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: movl $146, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB16_2 ; CHECK-NEXT: # %bb.4: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB16_2: # %entry ; CHECK-NEXT: movl $804, %eax # imm = 0x324 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB16_3 ; CHECK-NEXT: # %bb.5: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB16_3: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB16_6: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: bt_order_by_weight: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB16_1 ; NOOPT-NEXT: jmp .LBB16_5 ; NOOPT-NEXT: .LBB16_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $1, %eax ; NOOPT-NEXT: je .LBB16_2 ; NOOPT-NEXT: jmp .LBB16_6 ; NOOPT-NEXT: .LBB16_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB16_3 ; NOOPT-NEXT: jmp .LBB16_7 ; NOOPT-NEXT: .LBB16_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB16_1 ; NOOPT-NEXT: jmp .LBB16_8 ; NOOPT-NEXT: .LBB16_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $4, %eax ; NOOPT-NEXT: je .LBB16_2 ; NOOPT-NEXT: jmp .LBB16_9 ; NOOPT-NEXT: .LBB16_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $5, %eax ; NOOPT-NEXT: je .LBB16_3 ; NOOPT-NEXT: jmp .LBB16_10 ; NOOPT-NEXT: .LBB16_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $6, %eax ; NOOPT-NEXT: je .LBB16_1 ; NOOPT-NEXT: jmp .LBB16_11 ; NOOPT-NEXT: .LBB16_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $7, %eax ; NOOPT-NEXT: je .LBB16_2 ; NOOPT-NEXT: jmp .LBB16_12 ; NOOPT-NEXT: .LBB16_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: addl $-8, %eax ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: jb .LBB16_3 ; NOOPT-NEXT: jmp .LBB16_4 ; NOOPT-NEXT: .LBB16_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB16_4 ; NOOPT-NEXT: .LBB16_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB16_4 ; NOOPT-NEXT: .LBB16_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB16_4: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 3, label %bb0 i32 6, label %bb0 i32 1, label %bb1 i32 4, label %bb1 i32 7, label %bb1 i32 2, label %bb2 i32 5, label %bb2 i32 8, label %bb2 i32 9, label %bb2 ], !prof !1 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return return: ret void } !1 = !{!"branch_weights", ; Default: i32 1, ; Cases 0,3,6: i32 0, i32 0, i32 20, ; Cases 1,4,7: i32 4294967295, i32 2, i32 4294967295, ; Cases 2,5,8,9: i32 0, i32 0, i32 0, i32 20} ; Case 200 has the highest weight and should come first. 100 and 300 have the ; same weight, but 300 goes to the 'next' block, so should be last. define void @order_by_weight_and_fallthrough(i32 %x) { ; CHECK-LABEL: order_by_weight_and_fallthrough: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $200, %edi ; CHECK-NEXT: jne .LBB17_1 ; CHECK-NEXT: .LBB17_3: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB17_1: # %entry ; CHECK-NEXT: cmpl $100, %edi ; CHECK-NEXT: je .LBB17_4 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: cmpl $300, %edi # imm = 0x12C ; CHECK-NEXT: je .LBB17_3 ; CHECK-NEXT: # %bb.5: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB17_4: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: order_by_weight_and_fallthrough: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: subl $100, %edi ; NOOPT-NEXT: je .LBB17_2 ; NOOPT-NEXT: jmp .LBB17_4 ; NOOPT-NEXT: .LBB17_4: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $200, %eax ; NOOPT-NEXT: je .LBB17_1 ; NOOPT-NEXT: jmp .LBB17_5 ; NOOPT-NEXT: .LBB17_5: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $300, %eax # imm = 0x12C ; NOOPT-NEXT: jne .LBB17_3 ; NOOPT-NEXT: jmp .LBB17_1 ; NOOPT-NEXT: .LBB17_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB17_3 ; NOOPT-NEXT: .LBB17_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB17_3: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 100, label %bb1 i32 200, label %bb0 i32 300, label %bb0 ], !prof !2 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return return: ret void } !2 = !{!"branch_weights", ; Default: i32 1, ; Case 100: i32 10, ; Case 200: i32 1000, ; Case 300: i32 10} ; Make sure to pick a pivot in the middle also with zero-weight cases. define void @zero_weight_tree(i32 %x) { ; CHECK-LABEL: zero_weight_tree: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $29, %edi ; CHECK-NEXT: jg .LBB18_5 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: testl %edi, %edi ; CHECK-NEXT: jne .LBB18_2 ; CHECK-NEXT: # %bb.9: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB18_5: # %entry ; CHECK-NEXT: cmpl $50, %edi ; CHECK-NEXT: jne .LBB18_6 ; CHECK-NEXT: # %bb.12: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB18_2: # %entry ; CHECK-NEXT: cmpl $10, %edi ; CHECK-NEXT: je .LBB18_10 ; CHECK-NEXT: # %bb.3: # %entry ; CHECK-NEXT: cmpl $20, %edi ; CHECK-NEXT: jne .LBB18_13 ; CHECK-NEXT: # %bb.4: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB18_6: # %entry ; CHECK-NEXT: cmpl $30, %edi ; CHECK-NEXT: je .LBB18_11 ; CHECK-NEXT: # %bb.7: # %entry ; CHECK-NEXT: cmpl $40, %edi ; CHECK-NEXT: je .LBB18_8 ; CHECK-NEXT: .LBB18_13: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB18_10: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB18_11: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB18_8: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: zero_weight_tree: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB18_1 ; NOOPT-NEXT: jmp .LBB18_8 ; NOOPT-NEXT: .LBB18_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $10, %eax ; NOOPT-NEXT: je .LBB18_2 ; NOOPT-NEXT: jmp .LBB18_9 ; NOOPT-NEXT: .LBB18_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $20, %eax ; NOOPT-NEXT: je .LBB18_3 ; NOOPT-NEXT: jmp .LBB18_10 ; NOOPT-NEXT: .LBB18_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $30, %eax ; NOOPT-NEXT: je .LBB18_4 ; NOOPT-NEXT: jmp .LBB18_11 ; NOOPT-NEXT: .LBB18_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $40, %eax ; NOOPT-NEXT: je .LBB18_5 ; NOOPT-NEXT: jmp .LBB18_12 ; NOOPT-NEXT: .LBB18_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $50, %eax ; NOOPT-NEXT: je .LBB18_6 ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB18_7 ; NOOPT-NEXT: .LBB18_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB18_7: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 10, label %bb1 i32 20, label %bb2 i32 30, label %bb3 i32 40, label %bb4 i32 50, label %bb5 ], !prof !3 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return return: ret void } !3 = !{!"branch_weights", i32 1, i32 10, i32 0, i32 0, i32 0, i32 0, i32 10} ; Without branch probabilities, the pivot would be 40, since that would yield ; equal-sized sub-trees. When taking weights into account, case 70 becomes the ; pivot. Since there is room for 3 cases in a leaf, cases 50 and 60 are also ; included in the right-hand side because that doesn't reduce their rank. define void @left_leaning_weight_balanced_tree(i32 %x) { ; CHECK-LABEL: left_leaning_weight_balanced_tree: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $49, %edi ; CHECK-NEXT: jle .LBB19_1 ; CHECK-NEXT: # %bb.11: # %entry ; CHECK-NEXT: cmpl $70, %edi ; CHECK-NEXT: jne .LBB19_12 ; CHECK-NEXT: .LBB19_14: # %bb6 ; CHECK-NEXT: movl $6, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_1: # %entry ; CHECK-NEXT: cmpl $9, %edi ; CHECK-NEXT: jg .LBB19_4 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: testl %edi, %edi ; CHECK-NEXT: jne .LBB19_18 ; CHECK-NEXT: # %bb.3: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_4: # %entry ; CHECK-NEXT: cmpl $29, %edi ; CHECK-NEXT: jg .LBB19_8 ; CHECK-NEXT: # %bb.5: # %entry ; CHECK-NEXT: cmpl $10, %edi ; CHECK-NEXT: je .LBB19_15 ; CHECK-NEXT: # %bb.6: # %entry ; CHECK-NEXT: cmpl $20, %edi ; CHECK-NEXT: jne .LBB19_18 ; CHECK-NEXT: # %bb.7: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_12: # %entry ; CHECK-NEXT: cmpl $50, %edi ; CHECK-NEXT: je .LBB19_17 ; CHECK-NEXT: # %bb.13: # %entry ; CHECK-NEXT: cmpl $60, %edi ; CHECK-NEXT: je .LBB19_14 ; CHECK-NEXT: jmp .LBB19_18 ; CHECK-NEXT: .LBB19_8: # %entry ; CHECK-NEXT: cmpl $30, %edi ; CHECK-NEXT: je .LBB19_16 ; CHECK-NEXT: # %bb.9: # %entry ; CHECK-NEXT: cmpl $40, %edi ; CHECK-NEXT: jne .LBB19_18 ; CHECK-NEXT: # %bb.10: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_15: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_16: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_17: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB19_18: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: left_leaning_weight_balanced_tree: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB19_1 ; NOOPT-NEXT: jmp .LBB19_9 ; NOOPT-NEXT: .LBB19_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $10, %eax ; NOOPT-NEXT: je .LBB19_2 ; NOOPT-NEXT: jmp .LBB19_10 ; NOOPT-NEXT: .LBB19_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $20, %eax ; NOOPT-NEXT: je .LBB19_3 ; NOOPT-NEXT: jmp .LBB19_11 ; NOOPT-NEXT: .LBB19_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $30, %eax ; NOOPT-NEXT: je .LBB19_4 ; NOOPT-NEXT: jmp .LBB19_12 ; NOOPT-NEXT: .LBB19_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $40, %eax ; NOOPT-NEXT: je .LBB19_5 ; NOOPT-NEXT: jmp .LBB19_13 ; NOOPT-NEXT: .LBB19_13: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $50, %eax ; NOOPT-NEXT: je .LBB19_6 ; NOOPT-NEXT: jmp .LBB19_14 ; NOOPT-NEXT: .LBB19_14: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $60, %eax ; NOOPT-NEXT: je .LBB19_7 ; NOOPT-NEXT: jmp .LBB19_15 ; NOOPT-NEXT: .LBB19_15: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $70, %eax ; NOOPT-NEXT: je .LBB19_7 ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB19_8 ; NOOPT-NEXT: .LBB19_7: # %bb6 ; NOOPT-NEXT: movl $6, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB19_8: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 10, label %bb1 i32 20, label %bb2 i32 30, label %bb3 i32 40, label %bb4 i32 50, label %bb5 i32 60, label %bb6 i32 70, label %bb6 ], !prof !4 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return bb6: tail call void @g(i32 6) br label %return bb7: tail call void @g(i32 7) br label %return return: ret void } !4 = !{!"branch_weights", i32 1, i32 10, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1000} ; Same as the previous test, except case 50 has higher rank to the left than it ; would have on the right. Case 60 would have the same rank on both sides, so is ; moved into the leaf. define void @left_leaning_weight_balanced_tree2(i32 %x) { ; CHECK-LABEL: left_leaning_weight_balanced_tree2: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $59, %edi ; CHECK-NEXT: jle .LBB20_1 ; CHECK-NEXT: # %bb.10: # %entry ; CHECK-NEXT: cmpl $70, %edi ; CHECK-NEXT: jne .LBB20_11 ; CHECK-NEXT: .LBB20_12: # %bb6 ; CHECK-NEXT: movl $6, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_1: # %entry ; CHECK-NEXT: cmpl $29, %edi ; CHECK-NEXT: jle .LBB20_2 ; CHECK-NEXT: # %bb.6: # %entry ; CHECK-NEXT: cmpl $50, %edi ; CHECK-NEXT: jne .LBB20_7 ; CHECK-NEXT: # %bb.16: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_11: # %entry ; CHECK-NEXT: cmpl $60, %edi ; CHECK-NEXT: je .LBB20_12 ; CHECK-NEXT: jmp .LBB20_17 ; CHECK-NEXT: .LBB20_2: # %entry ; CHECK-NEXT: testl %edi, %edi ; CHECK-NEXT: jne .LBB20_3 ; CHECK-NEXT: # %bb.13: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_3: # %entry ; CHECK-NEXT: cmpl $10, %edi ; CHECK-NEXT: je .LBB20_14 ; CHECK-NEXT: # %bb.4: # %entry ; CHECK-NEXT: cmpl $20, %edi ; CHECK-NEXT: jne .LBB20_17 ; CHECK-NEXT: # %bb.5: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_7: # %entry ; CHECK-NEXT: cmpl $30, %edi ; CHECK-NEXT: je .LBB20_15 ; CHECK-NEXT: # %bb.8: # %entry ; CHECK-NEXT: cmpl $40, %edi ; CHECK-NEXT: jne .LBB20_17 ; CHECK-NEXT: # %bb.9: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_14: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_15: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB20_17: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: left_leaning_weight_balanced_tree2: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB20_1 ; NOOPT-NEXT: jmp .LBB20_9 ; NOOPT-NEXT: .LBB20_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $10, %eax ; NOOPT-NEXT: je .LBB20_2 ; NOOPT-NEXT: jmp .LBB20_10 ; NOOPT-NEXT: .LBB20_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $20, %eax ; NOOPT-NEXT: je .LBB20_3 ; NOOPT-NEXT: jmp .LBB20_11 ; NOOPT-NEXT: .LBB20_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $30, %eax ; NOOPT-NEXT: je .LBB20_4 ; NOOPT-NEXT: jmp .LBB20_12 ; NOOPT-NEXT: .LBB20_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $40, %eax ; NOOPT-NEXT: je .LBB20_5 ; NOOPT-NEXT: jmp .LBB20_13 ; NOOPT-NEXT: .LBB20_13: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $50, %eax ; NOOPT-NEXT: je .LBB20_6 ; NOOPT-NEXT: jmp .LBB20_14 ; NOOPT-NEXT: .LBB20_14: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $60, %eax ; NOOPT-NEXT: je .LBB20_7 ; NOOPT-NEXT: jmp .LBB20_15 ; NOOPT-NEXT: .LBB20_15: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $70, %eax ; NOOPT-NEXT: je .LBB20_7 ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB20_8 ; NOOPT-NEXT: .LBB20_7: # %bb6 ; NOOPT-NEXT: movl $6, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB20_8: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 10, label %bb1 i32 20, label %bb2 i32 30, label %bb3 i32 40, label %bb4 i32 50, label %bb5 i32 60, label %bb6 i32 70, label %bb6 ], !prof !5 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return bb6: tail call void @g(i32 6) br label %return bb7: tail call void @g(i32 7) br label %return return: ret void } !5 = !{!"branch_weights", i32 1, i32 10, i32 1, i32 1, i32 1, i32 1, i32 90, i32 70, i32 1000} ; Analogous to left_leaning_weight_balanced_tree. define void @right_leaning_weight_balanced_tree(i32 %x) { ; CHECK-LABEL: right_leaning_weight_balanced_tree: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $19, %edi ; CHECK-NEXT: jg .LBB21_4 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: testl %edi, %edi ; CHECK-NEXT: jne .LBB21_2 ; CHECK-NEXT: # %bb.13: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_4: # %entry ; CHECK-NEXT: cmpl $49, %edi ; CHECK-NEXT: jle .LBB21_5 ; CHECK-NEXT: # %bb.9: # %entry ; CHECK-NEXT: cmpl $70, %edi ; CHECK-NEXT: jne .LBB21_10 ; CHECK-NEXT: .LBB21_12: # %bb6 ; CHECK-NEXT: movl $6, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_5: # %entry ; CHECK-NEXT: cmpl $20, %edi ; CHECK-NEXT: je .LBB21_14 ; CHECK-NEXT: # %bb.6: # %entry ; CHECK-NEXT: cmpl $30, %edi ; CHECK-NEXT: je .LBB21_15 ; CHECK-NEXT: # %bb.7: # %entry ; CHECK-NEXT: cmpl $40, %edi ; CHECK-NEXT: jne .LBB21_17 ; CHECK-NEXT: # %bb.8: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_10: # %entry ; CHECK-NEXT: cmpl $50, %edi ; CHECK-NEXT: je .LBB21_16 ; CHECK-NEXT: # %bb.11: # %entry ; CHECK-NEXT: cmpl $60, %edi ; CHECK-NEXT: je .LBB21_12 ; CHECK-NEXT: jmp .LBB21_17 ; CHECK-NEXT: .LBB21_14: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_15: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_2: # %entry ; CHECK-NEXT: cmpl $10, %edi ; CHECK-NEXT: jne .LBB21_17 ; CHECK-NEXT: # %bb.3: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB21_17: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB21_16: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: right_leaning_weight_balanced_tree: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB21_1 ; NOOPT-NEXT: jmp .LBB21_9 ; NOOPT-NEXT: .LBB21_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $10, %eax ; NOOPT-NEXT: je .LBB21_2 ; NOOPT-NEXT: jmp .LBB21_10 ; NOOPT-NEXT: .LBB21_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $20, %eax ; NOOPT-NEXT: je .LBB21_3 ; NOOPT-NEXT: jmp .LBB21_11 ; NOOPT-NEXT: .LBB21_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $30, %eax ; NOOPT-NEXT: je .LBB21_4 ; NOOPT-NEXT: jmp .LBB21_12 ; NOOPT-NEXT: .LBB21_12: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $40, %eax ; NOOPT-NEXT: je .LBB21_5 ; NOOPT-NEXT: jmp .LBB21_13 ; NOOPT-NEXT: .LBB21_13: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $50, %eax ; NOOPT-NEXT: je .LBB21_6 ; NOOPT-NEXT: jmp .LBB21_14 ; NOOPT-NEXT: .LBB21_14: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $60, %eax ; NOOPT-NEXT: je .LBB21_7 ; NOOPT-NEXT: jmp .LBB21_15 ; NOOPT-NEXT: .LBB21_15: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $70, %eax ; NOOPT-NEXT: je .LBB21_7 ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB21_8 ; NOOPT-NEXT: .LBB21_7: # %bb6 ; NOOPT-NEXT: movl $6, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB21_8: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ i32 0, label %bb0 i32 10, label %bb1 i32 20, label %bb2 i32 30, label %bb3 i32 40, label %bb4 i32 50, label %bb5 i32 60, label %bb6 i32 70, label %bb6 ], !prof !6 bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return bb6: tail call void @g(i32 6) br label %return bb7: tail call void @g(i32 7) br label %return return: ret void } !6 = !{!"branch_weights", i32 1, i32 1000, i32 1, i32 1, i32 1, i32 1, i32 1, i32 1, i32 10} ; If the tree were balanced based on number of clusters, {0-3,100} would go on ; the left and {200,300} on the right. However, the jump table weights as much ; as its components, so 100 is selected as the pivot. define void @jump_table_affects_balance(i32 %x) { ; CHECK-LABEL: jump_table_affects_balance: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: cmpl $99, %edi ; CHECK-NEXT: jg .LBB22_3 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: ja .LBB22_10 ; CHECK-NEXT: # %bb.2: # %entry ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: jmpq *.LJTI22_0(,%rax,8) ; CHECK-NEXT: .LBB22_9: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB22_3: # %entry ; CHECK-NEXT: cmpl $300, %edi # imm = 0x12C ; CHECK-NEXT: je .LBB22_8 ; CHECK-NEXT: # %bb.4: # %entry ; CHECK-NEXT: cmpl $200, %edi ; CHECK-NEXT: je .LBB22_7 ; CHECK-NEXT: # %bb.5: # %entry ; CHECK-NEXT: cmpl $100, %edi ; CHECK-NEXT: jne .LBB22_10 ; CHECK-NEXT: .LBB22_6: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB22_8: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB22_7: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB22_10: # %return ; CHECK-NEXT: retq ; ; NOOPT-LABEL: jump_table_affects_balance: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: testl %edi, %edi ; NOOPT-NEXT: je .LBB22_1 ; NOOPT-NEXT: jmp .LBB22_6 ; NOOPT-NEXT: .LBB22_6: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $1, %eax ; NOOPT-NEXT: je .LBB22_2 ; NOOPT-NEXT: jmp .LBB22_7 ; NOOPT-NEXT: .LBB22_7: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: je .LBB22_3 ; NOOPT-NEXT: jmp .LBB22_8 ; NOOPT-NEXT: .LBB22_8: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: je .LBB22_4 ; NOOPT-NEXT: jmp .LBB22_9 ; NOOPT-NEXT: .LBB22_9: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $100, %eax ; NOOPT-NEXT: je .LBB22_1 ; NOOPT-NEXT: jmp .LBB22_10 ; NOOPT-NEXT: .LBB22_10: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $200, %eax ; NOOPT-NEXT: je .LBB22_2 ; NOOPT-NEXT: jmp .LBB22_11 ; NOOPT-NEXT: .LBB22_11: # %entry ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $300, %eax # imm = 0x12C ; NOOPT-NEXT: je .LBB22_3 ; NOOPT-NEXT: jmp .LBB22_5 ; NOOPT-NEXT: .LBB22_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB22_5 ; NOOPT-NEXT: .LBB22_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB22_5 ; NOOPT-NEXT: .LBB22_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB22_5 ; NOOPT-NEXT: .LBB22_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB22_5: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %x, label %return [ ; Jump table: i32 0, label %bb0 i32 1, label %bb1 i32 2, label %bb2 i32 3, label %bb3 i32 100, label %bb0 i32 200, label %bb1 i32 300, label %bb2 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return return: ret void } ; Don't assert due to truncating the bitwidth (64) to i4 when checking ; that the bit-test range fits in a word. define void @pr23738(i4 %x) { ; CHECK-LABEL: pr23738: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: movl %edi, %eax ; CHECK-NEXT: andb $15, %al ; CHECK-NEXT: cmpb $11, %al ; CHECK-NEXT: ja .LBB23_2 ; CHECK-NEXT: # %bb.1: # %entry ; CHECK-NEXT: andl $15, %edi ; CHECK-NEXT: movl $2051, %eax # imm = 0x803 ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB23_2 ; CHECK-NEXT: # %bb.3: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB23_2: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: pr23738: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movb %dil, %al ; NOOPT-NEXT: movb %al, {{[-0-9]+}}(%r{{[sb]}}p) # 1-byte Spill ; NOOPT-NEXT: andb $15, %al ; NOOPT-NEXT: subb $11, %al ; NOOPT-NEXT: je .LBB23_2 ; NOOPT-NEXT: jmp .LBB23_4 ; NOOPT-NEXT: .LBB23_4: # %entry ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: andb $15, %al ; NOOPT-NEXT: subb $2, %al ; NOOPT-NEXT: jb .LBB23_2 ; NOOPT-NEXT: jmp .LBB23_1 ; NOOPT-NEXT: .LBB23_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB23_3 ; NOOPT-NEXT: .LBB23_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB23_3: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i4 %x, label %bb0 [ i4 0, label %bb1 i4 1, label %bb1 i4 -5, label %bb1 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return return: ret void } ; The switch is lowered with bit tests. Since the case range is contiguous, the ; second bit test is redundant and can be skipped. Check that we don't update ; the phi node with an incoming value from the MBB of the skipped bit test ; (-verify-machine-instrs cathces this). define i32 @pr27135(i32 %i) { ; CHECK-LABEL: pr27135: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: xorl %eax, %eax ; CHECK-NEXT: testb %al, %al ; CHECK-NEXT: jne .LBB24_5 ; CHECK-NEXT: # %bb.1: # %sw ; CHECK-NEXT: movl $1, %eax ; CHECK-NEXT: addl $-96, %edi ; CHECK-NEXT: cmpl $5, %edi ; CHECK-NEXT: jbe .LBB24_2 ; CHECK-NEXT: .LBB24_5: # %end ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB24_2: # %sw ; CHECK-NEXT: movl $19, %eax ; CHECK-NEXT: btl %edi, %eax ; CHECK-NEXT: jae .LBB24_3 ; CHECK-NEXT: # %bb.4: # %sw.bb2 ; CHECK-NEXT: .LBB24_3: # %sw.bb ; ; NOOPT-LABEL: pr27135: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: movl %edi, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: xorl %eax, %eax ; NOOPT-NEXT: # implicit-def: $cl ; NOOPT-NEXT: testb $1, %cl ; NOOPT-NEXT: movl %eax, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: jne .LBB24_1 ; NOOPT-NEXT: jmp .LBB24_4 ; NOOPT-NEXT: .LBB24_1: # %sw ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: movl $1, %ecx ; NOOPT-NEXT: movl %ecx, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: addl $-96, %eax ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: jb .LBB24_3 ; NOOPT-NEXT: jmp .LBB24_5 ; NOOPT-NEXT: .LBB24_5: # %sw ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: addl $-98, %eax ; NOOPT-NEXT: subl $2, %eax ; NOOPT-NEXT: jb .LBB24_2 ; NOOPT-NEXT: jmp .LBB24_6 ; NOOPT-NEXT: .LBB24_6: # %sw ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: subl $100, %eax ; NOOPT-NEXT: je .LBB24_3 ; NOOPT-NEXT: jmp .LBB24_7 ; NOOPT-NEXT: .LBB24_7: # %sw ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %ecx # 4-byte Reload ; NOOPT-NEXT: subl $101, %ecx ; NOOPT-NEXT: movl %eax, {{[-0-9]+}}(%r{{[sb]}}p) # 4-byte Spill ; NOOPT-NEXT: jne .LBB24_4 ; NOOPT-NEXT: jmp .LBB24_2 ; NOOPT-NEXT: .LBB24_2: # %sw.bb ; NOOPT-NEXT: .LBB24_3: # %sw.bb2 ; NOOPT-NEXT: .LBB24_4: # %end ; NOOPT-NEXT: movl {{[-0-9]+}}(%r{{[sb]}}p), %eax # 4-byte Reload ; NOOPT-NEXT: retq entry: br i1 undef, label %sw, label %end sw: switch i32 %i, label %end [ i32 99, label %sw.bb i32 98, label %sw.bb i32 101, label %sw.bb i32 97, label %sw.bb2 i32 96, label %sw.bb2 i32 100, label %sw.bb2 ] sw.bb: unreachable sw.bb2: unreachable end: %p = phi i32 [ 1, %sw ], [ 0, %entry ] ret i32 %p } ; Since the default is unreachable, either cluster will be reached. ; Only one comparison should be emitted. define void @range_with_unreachable_fallthrough(i32 %i) { ; CHECK-LABEL: range_with_unreachable_fallthrough: ; CHECK: # %bb.0: # %entry ; CHECK-NEXT: addl $-4, %edi ; CHECK-NEXT: cmpl $3, %edi ; CHECK-NEXT: jae .LBB25_1 ; CHECK-NEXT: # %bb.2: # %bb2 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB25_1: # %bb1 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: range_with_unreachable_fallthrough: ; NOOPT: # %bb.0: # %entry ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movl %edi, %eax ; NOOPT-NEXT: decl %eax ; NOOPT-NEXT: subl $3, %eax ; NOOPT-NEXT: jb .LBB25_1 ; NOOPT-NEXT: jmp .LBB25_5 ; NOOPT-NEXT: .LBB25_5: # %entry ; NOOPT-NEXT: jmp .LBB25_2 ; NOOPT-NEXT: .LBB25_1: # %bb1 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB25_4 ; NOOPT-NEXT: .LBB25_2: # %bb2 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB25_4 ; NOOPT-NEXT: # %bb.3: # %default ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: .LBB25_4: # %return ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq entry: switch i32 %i, label %default [ i32 1, label %bb1 i32 2, label %bb1 i32 3, label %bb1 i32 4, label %bb2 i32 5, label %bb2 i32 6, label %bb2 ] bb1: tail call void @g(i32 0) br label %return bb2: tail call void @g(i32 1) br label %return default: unreachable return: ret void } ; A switch over a small type (i8) should be extended to avoid truncation ; instructions. define void @switch_i8(i32 %a) { ; CHECK-LABEL: switch_i8: ; CHECK: # %bb.0: ; CHECK-NEXT: # kill: def $edi killed $edi def $rdi ; CHECK-NEXT: andl $127, %edi ; CHECK-NEXT: leal -1(%rdi), %eax ; CHECK-NEXT: cmpl $8, %eax ; CHECK-NEXT: ja .LBB26_1 ; CHECK-NEXT: # %bb.10: ; CHECK-NEXT: jmpq *.LJTI26_0(,%rax,8) ; CHECK-NEXT: .LBB26_4: # %bb0 ; CHECK-NEXT: xorl %edi, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB26_1: ; CHECK-NEXT: cmpl $13, %edi ; CHECK-NEXT: je .LBB26_8 ; CHECK-NEXT: # %bb.2: ; CHECK-NEXT: cmpl $42, %edi ; CHECK-NEXT: jne .LBB26_9 ; CHECK-NEXT: # %bb.3: # %bb5 ; CHECK-NEXT: movl $5, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB26_9: # %return ; CHECK-NEXT: retq ; CHECK-NEXT: .LBB26_5: # %bb1 ; CHECK-NEXT: movl $1, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB26_6: # %bb2 ; CHECK-NEXT: movl $2, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB26_7: # %bb3 ; CHECK-NEXT: movl $3, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; CHECK-NEXT: .LBB26_8: # %bb4 ; CHECK-NEXT: movl $4, %edi ; CHECK-NEXT: jmp g@PLT # TAILCALL ; ; NOOPT-LABEL: switch_i8: ; NOOPT: # %bb.0: ; NOOPT-NEXT: pushq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 16 ; NOOPT-NEXT: movb %dil, %al ; NOOPT-NEXT: andb $127, %al ; NOOPT-NEXT: movb %al, {{[-0-9]+}}(%r{{[sb]}}p) # 1-byte Spill ; NOOPT-NEXT: subb $1, %al ; NOOPT-NEXT: je .LBB26_1 ; NOOPT-NEXT: jmp .LBB26_8 ; NOOPT-NEXT: .LBB26_8: ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: subb $3, %al ; NOOPT-NEXT: je .LBB26_2 ; NOOPT-NEXT: jmp .LBB26_9 ; NOOPT-NEXT: .LBB26_9: ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: subb $7, %al ; NOOPT-NEXT: je .LBB26_3 ; NOOPT-NEXT: jmp .LBB26_10 ; NOOPT-NEXT: .LBB26_10: ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: subb $9, %al ; NOOPT-NEXT: je .LBB26_4 ; NOOPT-NEXT: jmp .LBB26_11 ; NOOPT-NEXT: .LBB26_11: ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: subb $13, %al ; NOOPT-NEXT: je .LBB26_5 ; NOOPT-NEXT: jmp .LBB26_12 ; NOOPT-NEXT: .LBB26_12: ; NOOPT-NEXT: movb {{[-0-9]+}}(%r{{[sb]}}p), %al # 1-byte Reload ; NOOPT-NEXT: subb $42, %al ; NOOPT-NEXT: je .LBB26_6 ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_1: # %bb0 ; NOOPT-NEXT: xorl %edi, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_2: # %bb1 ; NOOPT-NEXT: movl $1, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_3: # %bb2 ; NOOPT-NEXT: movl $2, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_4: # %bb3 ; NOOPT-NEXT: movl $3, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_5: # %bb4 ; NOOPT-NEXT: movl $4, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: jmp .LBB26_7 ; NOOPT-NEXT: .LBB26_6: # %bb5 ; NOOPT-NEXT: movl $5, %edi ; NOOPT-NEXT: callq g@PLT ; NOOPT-NEXT: .LBB26_7: # %return ; NOOPT-NEXT: popq %rax ; NOOPT-NEXT: .cfi_def_cfa_offset 8 ; NOOPT-NEXT: retq %and = and i32 %a, 127 %trunc = trunc i32 %and to i8 switch i8 %trunc, label %return [ i8 1, label %bb0 i8 3, label %bb1 i8 7, label %bb2 i8 9, label %bb3 i8 13, label %bb4 i8 42, label %bb5 ] bb0: tail call void @g(i32 0) br label %return bb1: tail call void @g(i32 1) br label %return bb2: tail call void @g(i32 2) br label %return bb3: tail call void @g(i32 3) br label %return bb4: tail call void @g(i32 4) br label %return bb5: tail call void @g(i32 5) br label %return return: ret void }