; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py ; RUN: llc -mtriple=i386-linux-gnu -verify-machineinstrs %s -o - | FileCheck %s --check-prefixes=32-ALL,32-GOOD-RA ; RUN: llc -mtriple=i386-linux-gnu -verify-machineinstrs -pre-RA-sched=fast %s -o - | FileCheck %s --check-prefixes=32-ALL,32-FAST-RA ; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs %s -o - | FileCheck %s --check-prefix=64-ALL ; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs -pre-RA-sched=fast %s -o - | FileCheck %s --check-prefix=64-ALL ; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs -mattr=+sahf %s -o - | FileCheck %s --check-prefix=64-ALL ; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs -mattr=+sahf -pre-RA-sched=fast %s -o - | FileCheck %s --check-prefix=64-ALL ; RUN: llc -mtriple=x86_64-linux-gnu -verify-machineinstrs -mcpu=corei7 %s -o - | FileCheck %s --check-prefix=64-ALL declare i32 @foo() declare i32 @bar(i64) ; In the following case when using fast scheduling we get a long chain of ; EFLAGS save/restore due to a sequence of: ; cmpxchg8b (implicit-def eflags) ; eax = copy eflags ; adjcallstackdown32 ; ... ; use of eax ; During PEI the adjcallstackdown32 is replaced with the subl which ; clobbers eflags, effectively interfering in the liveness interval. However, ; we then promote these copies into independent conditions in GPRs that avoids ; repeated saving and restoring logic and can be trivially managed by the ; register allocator. define i64 @test_intervening_call(ptr %foo, i64 %bar, i64 %baz) nounwind { ; 32-GOOD-RA-LABEL: test_intervening_call: ; 32-GOOD-RA: # %bb.0: # %entry ; 32-GOOD-RA-NEXT: pushl %ebx ; 32-GOOD-RA-NEXT: pushl %esi ; 32-GOOD-RA-NEXT: pushl %eax ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %eax ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %edx ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %ebx ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %ecx ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %esi ; 32-GOOD-RA-NEXT: lock cmpxchg8b (%esi) ; 32-GOOD-RA-NEXT: setne %bl ; 32-GOOD-RA-NEXT: subl $8, %esp ; 32-GOOD-RA-NEXT: pushl %edx ; 32-GOOD-RA-NEXT: pushl %eax ; 32-GOOD-RA-NEXT: calll bar@PLT ; 32-GOOD-RA-NEXT: addl $16, %esp ; 32-GOOD-RA-NEXT: testb %bl, %bl ; 32-GOOD-RA-NEXT: jne .LBB0_3 ; 32-GOOD-RA-NEXT: # %bb.1: # %t ; 32-GOOD-RA-NEXT: movl $42, %eax ; 32-GOOD-RA-NEXT: jmp .LBB0_2 ; 32-GOOD-RA-NEXT: .LBB0_3: # %f ; 32-GOOD-RA-NEXT: xorl %eax, %eax ; 32-GOOD-RA-NEXT: .LBB0_2: # %t ; 32-GOOD-RA-NEXT: xorl %edx, %edx ; 32-GOOD-RA-NEXT: addl $4, %esp ; 32-GOOD-RA-NEXT: popl %esi ; 32-GOOD-RA-NEXT: popl %ebx ; 32-GOOD-RA-NEXT: retl ; ; 32-FAST-RA-LABEL: test_intervening_call: ; 32-FAST-RA: # %bb.0: # %entry ; 32-FAST-RA-NEXT: pushl %ebx ; 32-FAST-RA-NEXT: pushl %esi ; 32-FAST-RA-NEXT: pushl %eax ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %esi ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %ebx ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %ecx ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %eax ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %edx ; 32-FAST-RA-NEXT: lock cmpxchg8b (%esi) ; 32-FAST-RA-NEXT: setne %bl ; 32-FAST-RA-NEXT: subl $8, %esp ; 32-FAST-RA-NEXT: pushl %edx ; 32-FAST-RA-NEXT: pushl %eax ; 32-FAST-RA-NEXT: calll bar@PLT ; 32-FAST-RA-NEXT: addl $16, %esp ; 32-FAST-RA-NEXT: testb %bl, %bl ; 32-FAST-RA-NEXT: jne .LBB0_3 ; 32-FAST-RA-NEXT: # %bb.1: # %t ; 32-FAST-RA-NEXT: movl $42, %eax ; 32-FAST-RA-NEXT: jmp .LBB0_2 ; 32-FAST-RA-NEXT: .LBB0_3: # %f ; 32-FAST-RA-NEXT: xorl %eax, %eax ; 32-FAST-RA-NEXT: .LBB0_2: # %t ; 32-FAST-RA-NEXT: xorl %edx, %edx ; 32-FAST-RA-NEXT: addl $4, %esp ; 32-FAST-RA-NEXT: popl %esi ; 32-FAST-RA-NEXT: popl %ebx ; 32-FAST-RA-NEXT: retl ; ; 64-ALL-LABEL: test_intervening_call: ; 64-ALL: # %bb.0: # %entry ; 64-ALL-NEXT: pushq %rbx ; 64-ALL-NEXT: movq %rsi, %rax ; 64-ALL-NEXT: lock cmpxchgq %rdx, (%rdi) ; 64-ALL-NEXT: setne %bl ; 64-ALL-NEXT: movq %rax, %rdi ; 64-ALL-NEXT: callq bar@PLT ; 64-ALL-NEXT: testb %bl, %bl ; 64-ALL-NEXT: jne .LBB0_2 ; 64-ALL-NEXT: # %bb.1: # %t ; 64-ALL-NEXT: movl $42, %eax ; 64-ALL-NEXT: popq %rbx ; 64-ALL-NEXT: retq ; 64-ALL-NEXT: .LBB0_2: # %f ; 64-ALL-NEXT: xorl %eax, %eax ; 64-ALL-NEXT: popq %rbx ; 64-ALL-NEXT: retq entry: %cx = cmpxchg ptr %foo, i64 %bar, i64 %baz seq_cst seq_cst %v = extractvalue { i64, i1 } %cx, 0 %p = extractvalue { i64, i1 } %cx, 1 call i32 @bar(i64 %v) br i1 %p, label %t, label %f t: ret i64 42 f: ret i64 0 } ; Interesting in producing a clobber without any function calls. define i32 @test_control_flow(ptr %p, i32 %i, i32 %j) nounwind { ; 32-ALL-LABEL: test_control_flow: ; 32-ALL: # %bb.0: # %entry ; 32-ALL-NEXT: movl {{[0-9]+}}(%esp), %eax ; 32-ALL-NEXT: cmpl {{[0-9]+}}(%esp), %eax ; 32-ALL-NEXT: jle .LBB1_6 ; 32-ALL-NEXT: # %bb.1: # %loop_start ; 32-ALL-NEXT: movl {{[0-9]+}}(%esp), %ecx ; 32-ALL-NEXT: .p2align 4, 0x90 ; 32-ALL-NEXT: .LBB1_2: # %while.condthread-pre-split.i ; 32-ALL-NEXT: # =>This Loop Header: Depth=1 ; 32-ALL-NEXT: # Child Loop BB1_3 Depth 2 ; 32-ALL-NEXT: movl (%ecx), %edx ; 32-ALL-NEXT: .p2align 4, 0x90 ; 32-ALL-NEXT: .LBB1_3: # %while.cond.i ; 32-ALL-NEXT: # Parent Loop BB1_2 Depth=1 ; 32-ALL-NEXT: # => This Inner Loop Header: Depth=2 ; 32-ALL-NEXT: movl %edx, %eax ; 32-ALL-NEXT: xorl %edx, %edx ; 32-ALL-NEXT: testl %eax, %eax ; 32-ALL-NEXT: je .LBB1_3 ; 32-ALL-NEXT: # %bb.4: # %while.body.i ; 32-ALL-NEXT: # in Loop: Header=BB1_2 Depth=1 ; 32-ALL-NEXT: lock cmpxchgl %eax, (%ecx) ; 32-ALL-NEXT: jne .LBB1_2 ; 32-ALL-NEXT: # %bb.5: ; 32-ALL-NEXT: xorl %eax, %eax ; 32-ALL-NEXT: .LBB1_6: # %cond.end ; 32-ALL-NEXT: retl ; ; 64-ALL-LABEL: test_control_flow: ; 64-ALL: # %bb.0: # %entry ; 64-ALL-NEXT: movl %esi, %eax ; 64-ALL-NEXT: cmpl %edx, %esi ; 64-ALL-NEXT: jle .LBB1_5 ; 64-ALL-NEXT: .p2align 4, 0x90 ; 64-ALL-NEXT: .LBB1_1: # %while.condthread-pre-split.i ; 64-ALL-NEXT: # =>This Loop Header: Depth=1 ; 64-ALL-NEXT: # Child Loop BB1_2 Depth 2 ; 64-ALL-NEXT: movl (%rdi), %ecx ; 64-ALL-NEXT: .p2align 4, 0x90 ; 64-ALL-NEXT: .LBB1_2: # %while.cond.i ; 64-ALL-NEXT: # Parent Loop BB1_1 Depth=1 ; 64-ALL-NEXT: # => This Inner Loop Header: Depth=2 ; 64-ALL-NEXT: movl %ecx, %eax ; 64-ALL-NEXT: xorl %ecx, %ecx ; 64-ALL-NEXT: testl %eax, %eax ; 64-ALL-NEXT: je .LBB1_2 ; 64-ALL-NEXT: # %bb.3: # %while.body.i ; 64-ALL-NEXT: # in Loop: Header=BB1_1 Depth=1 ; 64-ALL-NEXT: lock cmpxchgl %eax, (%rdi) ; 64-ALL-NEXT: jne .LBB1_1 ; 64-ALL-NEXT: # %bb.4: ; 64-ALL-NEXT: xorl %eax, %eax ; 64-ALL-NEXT: .LBB1_5: # %cond.end ; 64-ALL-NEXT: retq entry: %cmp = icmp sgt i32 %i, %j br i1 %cmp, label %loop_start, label %cond.end loop_start: br label %while.condthread-pre-split.i while.condthread-pre-split.i: %.pr.i = load i32, ptr %p, align 4 br label %while.cond.i while.cond.i: %0 = phi i32 [ %.pr.i, %while.condthread-pre-split.i ], [ 0, %while.cond.i ] %tobool.i = icmp eq i32 %0, 0 br i1 %tobool.i, label %while.cond.i, label %while.body.i while.body.i: %.lcssa = phi i32 [ %0, %while.cond.i ] %1 = cmpxchg ptr %p, i32 %.lcssa, i32 %.lcssa seq_cst seq_cst %2 = extractvalue { i32, i1 } %1, 1 br i1 %2, label %cond.end.loopexit, label %while.condthread-pre-split.i cond.end.loopexit: br label %cond.end cond.end: %cond = phi i32 [ %i, %entry ], [ 0, %cond.end.loopexit ] ret i32 %cond } ; This one is an interesting case because CMOV doesn't have a chain ; operand. Naive attempts to limit cmpxchg EFLAGS use are likely to fail here. define i32 @test_feed_cmov(ptr %addr, i32 %desired, i32 %new) nounwind { ; 32-GOOD-RA-LABEL: test_feed_cmov: ; 32-GOOD-RA: # %bb.0: # %entry ; 32-GOOD-RA-NEXT: pushl %ebx ; 32-GOOD-RA-NEXT: pushl %esi ; 32-GOOD-RA-NEXT: pushl %eax ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %eax ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %esi ; 32-GOOD-RA-NEXT: movl {{[0-9]+}}(%esp), %ecx ; 32-GOOD-RA-NEXT: lock cmpxchgl %esi, (%ecx) ; 32-GOOD-RA-NEXT: sete %bl ; 32-GOOD-RA-NEXT: calll foo@PLT ; 32-GOOD-RA-NEXT: testb %bl, %bl ; 32-GOOD-RA-NEXT: jne .LBB2_2 ; 32-GOOD-RA-NEXT: # %bb.1: # %entry ; 32-GOOD-RA-NEXT: movl %eax, %esi ; 32-GOOD-RA-NEXT: .LBB2_2: # %entry ; 32-GOOD-RA-NEXT: movl %esi, %eax ; 32-GOOD-RA-NEXT: addl $4, %esp ; 32-GOOD-RA-NEXT: popl %esi ; 32-GOOD-RA-NEXT: popl %ebx ; 32-GOOD-RA-NEXT: retl ; ; 32-FAST-RA-LABEL: test_feed_cmov: ; 32-FAST-RA: # %bb.0: # %entry ; 32-FAST-RA-NEXT: pushl %ebx ; 32-FAST-RA-NEXT: pushl %esi ; 32-FAST-RA-NEXT: pushl %eax ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %ecx ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %esi ; 32-FAST-RA-NEXT: movl {{[0-9]+}}(%esp), %eax ; 32-FAST-RA-NEXT: lock cmpxchgl %esi, (%ecx) ; 32-FAST-RA-NEXT: sete %bl ; 32-FAST-RA-NEXT: calll foo@PLT ; 32-FAST-RA-NEXT: testb %bl, %bl ; 32-FAST-RA-NEXT: jne .LBB2_2 ; 32-FAST-RA-NEXT: # %bb.1: # %entry ; 32-FAST-RA-NEXT: movl %eax, %esi ; 32-FAST-RA-NEXT: .LBB2_2: # %entry ; 32-FAST-RA-NEXT: movl %esi, %eax ; 32-FAST-RA-NEXT: addl $4, %esp ; 32-FAST-RA-NEXT: popl %esi ; 32-FAST-RA-NEXT: popl %ebx ; 32-FAST-RA-NEXT: retl ; ; 64-ALL-LABEL: test_feed_cmov: ; 64-ALL: # %bb.0: # %entry ; 64-ALL-NEXT: pushq %rbp ; 64-ALL-NEXT: pushq %rbx ; 64-ALL-NEXT: pushq %rax ; 64-ALL-NEXT: movl %edx, %ebx ; 64-ALL-NEXT: movl %esi, %eax ; 64-ALL-NEXT: lock cmpxchgl %edx, (%rdi) ; 64-ALL-NEXT: sete %bpl ; 64-ALL-NEXT: callq foo@PLT ; 64-ALL-NEXT: testb %bpl, %bpl ; 64-ALL-NEXT: cmovnel %ebx, %eax ; 64-ALL-NEXT: addq $8, %rsp ; 64-ALL-NEXT: popq %rbx ; 64-ALL-NEXT: popq %rbp ; 64-ALL-NEXT: retq entry: %res = cmpxchg ptr %addr, i32 %desired, i32 %new seq_cst seq_cst %success = extractvalue { i32, i1 } %res, 1 %rhs = call i32 @foo() %ret = select i1 %success, i32 %new, i32 %rhs ret i32 %ret }