; RUN: opt -verify-loop-info -irce-print-changed-loops -irce -S < %s 2>&1 | FileCheck %s
; RUN: opt -verify-loop-info -irce-print-changed-loops -passes='require<branch-prob>,irce' -S < %s 2>&1 | FileCheck %s
; CHECK-LABEL: irce: in function test_01: constrained Loop at depth 1 containing:
; CHECK-LABEL: irce: in function test_02: constrained Loop at depth 1 containing:
; CHECK-LABEL: irce: in function test_03: constrained Loop at depth 1 containing:
; CHECK-LABEL: irce: in function test_04: constrained Loop at depth 1 containing:
; CHECK-LABEL: irce: in function test_05: constrained Loop at depth 1 containing:
; This test used to demonstrate a miscompile: the outer loop's IV iterates in
; range of [2, 400) and the range check is done against value 331. Due to a bug
; in range intersection IRCE manages to eliminate the range check without
; inserting a postloop, which is incorrect. We treat the range of this test as
; an unsigned range and are able to intersect ranges correctly and insert a
; postloop.
define void @test_01() {
; CHECK-LABEL: test_01
; CHECK-NOT: preloop
; CHECK: range_check_block: ; preds = %inner_loop
; CHECK-NEXT: %range_check = icmp slt i32 %iv, 331
; CHECK-NEXT: br i1 true, label %loop_latch
; CHECK: loop_latch:
; CHECK-NEXT: %iv_next = add i32 %iv, 1
; CHECK-NEXT: %loop_cond = icmp ult i32 %iv_next, 400
; CHECK-NEXT: [[COND:%[^ ]+]] = icmp ult i32 %iv_next, 331
; CHECK-NEXT: br i1 [[COND]], label %loop_header, label %main.exit.selector
; CHECK: main.exit.selector: ; preds = %loop_latch
; CHECK-NEXT: %iv_next.lcssa = phi i32 [ %iv_next, %loop_latch ]
; CHECK-NEXT: %iv.lcssa = phi i32 [ %iv, %loop_latch ]
; CHECK-NEXT: [[MES_COND:%[^ ]+]] = icmp ult i32 %iv_next.lcssa, 400
; CHECK-NEXT: br i1 [[MES_COND]], label %main.pseudo.exit, label %exit
; CHECK: loop_latch.postloop: ; preds = %range_check_block.postloop
; CHECK-NEXT: %iv_next.postloop = add i32 %iv.postloop, 1
; CHECK-NEXT: %loop_cond.postloop = icmp ult i32 %iv_next.postloop, 400
; CHECK-NEXT: br i1 %loop_cond.postloop, label %loop_header.postloop, label %exit.loopexit
entry:
br label %loop_header
loop_header: ; preds = %loop_latch, %entry
%iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
%iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
%tmp2 = icmp sgt i32 %iv.prev, -1
br i1 %tmp2, label %loop_header.split.us, label %exit
loop_header.split.us: ; preds = %loop_header
br label %inner_loop
inner_loop: ; preds = %inner_loop, %loop_header.split.us
%inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
%inner_iv_next = add nuw nsw i32 %inner_iv, 1
%inner_cond = icmp ult i32 %inner_iv_next, 31
br i1 %inner_cond, label %inner_loop, label %range_check_block
exit: ; preds = %loop_latch, %loop_header
ret void
range_check_block: ; preds = %inner_loop
%range_check = icmp slt i32 %iv, 331
br i1 %range_check, label %loop_latch, label %deopt
loop_latch: ; preds = %range_check_block
%iv_next = add i32 %iv, 1
%loop_cond = icmp ult i32 %iv_next, 400
br i1 %loop_cond, label %loop_header, label %exit
deopt: ; preds = %range_check_block
ret void
}
; Similar to test_01, but here the range check is done against 450. No postloop
; is required.
define void @test_02() {
; CHECK-LABEL: test_02
; CHECK-NOT: preloop
; CHECK-NOT: postloop
; CHECK: range_check_block: ; preds = %inner_loop
; CHECK-NEXT: %range_check = icmp slt i32 %iv, 450
; CHECK-NEXT: br i1 true, label %loop_latch
; CHECK: loop_latch: ; preds = %range_check_block
; CHECK-NEXT: %iv_next = add i32 %iv, 1
; CHECK-NEXT: %loop_cond = icmp ult i32 %iv_next, 400
; CHECK-NEXT: br i1 %loop_cond, label %loop_header, label %exit
entry:
br label %loop_header
loop_header: ; preds = %loop_latch, %entry
%iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
%iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
%tmp2 = icmp sgt i32 %iv.prev, -1
br i1 %tmp2, label %loop_header.split.us, label %exit
loop_header.split.us: ; preds = %loop_header
br label %inner_loop
inner_loop: ; preds = %inner_loop, %loop_header.split.us
%inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
%inner_iv_next = add nuw nsw i32 %inner_iv, 1
%inner_cond = icmp ult i32 %inner_iv_next, 31
br i1 %inner_cond, label %inner_loop, label %range_check_block
exit: ; preds = %loop_latch, %loop_header
ret void
range_check_block: ; preds = %inner_loop
%range_check = icmp slt i32 %iv, 450
br i1 %range_check, label %loop_latch, label %deopt
loop_latch: ; preds = %range_check_block
%iv_next = add i32 %iv, 1
%loop_cond = icmp ult i32 %iv_next, 400
br i1 %loop_cond, label %loop_header, label %exit
deopt: ; preds = %range_check_block
ret void
}
; Range check is made against 0, so the safe iteration range is empty. IRCE
; should not apply to the inner loop. The condition %tmp2 can be eliminated.
define void @test_03() {
; CHECK-LABEL: test_03
; CHECK-NOT: preloop
; CHECK-NOT: postloop
; CHECK: %tmp2 = icmp sgt i32 %iv.prev, -1
; CHECK-NEXT: br i1 true, label %loop_header.split.us, label %exit
; CHECK: range_check_block:
; CHECK-NEXT: %range_check = icmp slt i32 %iv, 0
; CHECK-NEXT: br i1 %range_check, label %loop_latch, label %deopt
entry:
br label %loop_header
loop_header: ; preds = %loop_latch, %entry
%iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
%iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
%tmp2 = icmp sgt i32 %iv.prev, -1
br i1 %tmp2, label %loop_header.split.us, label %exit
loop_header.split.us: ; preds = %loop_header
br label %inner_loop
inner_loop: ; preds = %inner_loop, %loop_header.split.us
%inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
%inner_iv_next = add nuw nsw i32 %inner_iv, 1
%inner_cond = icmp ult i32 %inner_iv_next, 31
br i1 %inner_cond, label %inner_loop, label %range_check_block
exit: ; preds = %loop_latch, %loop_header
ret void
range_check_block: ; preds = %inner_loop
%range_check = icmp slt i32 %iv, 0
br i1 %range_check, label %loop_latch, label %deopt
loop_latch: ; preds = %range_check_block
%iv_next = add i32 %iv, 1
%loop_cond = icmp ult i32 %iv_next, 400
br i1 %loop_cond, label %loop_header, label %exit
deopt: ; preds = %range_check_block
ret void
}
; We can also properly eliminate range check against %n which is not always
; known positive.
define void @test_04(i32* %p) {
; CHECK-LABEL: test_04
; CHECK: entry
; CHECK-NOT: preloop
; CHECK: %tmp2 = icmp sgt i32 %iv.prev, -1
; CHECK-NEXT: br i1 true, label %loop_header.split.us, label %exit
; CHECK: range_check_block:
; CHECK-NEXT: %range_check = icmp slt i32 %iv, %n
; CHECK-NEXT: br i1 true, label %loop_latch, label %deopt
; CHECK: postloop:
entry:
%n = load i32, i32* %p
br label %loop_header
loop_header: ; preds = %loop_latch, %entry
%iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
%iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
%tmp2 = icmp sgt i32 %iv.prev, -1
br i1 %tmp2, label %loop_header.split.us, label %exit
loop_header.split.us: ; preds = %loop_header
br label %inner_loop
inner_loop: ; preds = %inner_loop, %loop_header.split.us
%inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
%inner_iv_next = add nuw nsw i32 %inner_iv, 1
%inner_cond = icmp ult i32 %inner_iv_next, 31
br i1 %inner_cond, label %inner_loop, label %range_check_block
exit: ; preds = %loop_latch, %loop_header
ret void
range_check_block: ; preds = %inner_loop
%range_check = icmp slt i32 %iv, %n
br i1 %range_check, label %loop_latch, label %deopt
loop_latch: ; preds = %range_check_block
%iv_next = add i32 %iv, 1
%loop_cond = icmp ult i32 %iv_next, 400
br i1 %loop_cond, label %loop_header, label %exit
deopt: ; preds = %range_check_block
ret void
}
; Same as test_04, but range guarantees that %n is positive. So we can safely
; intersect ranges (with insertion of postloop).
define void @test_05(i32* %p) {
; CHECK-LABEL: test_05
; CHECK-NOT: preloop
; CHECK: entry:
; CHECK-NEXT: %n = load i32, i32* %p, align 4, !range !
; CHECK-NEXT: %exit.mainloop.at = call i32 @llvm.umax.i32(i32 %n, i32 2)
; CHECK-NEXT: [[CMP_2:%[^ ]+]] = icmp ult i32 2, %exit.mainloop.at
; CHECK-NEXT: br i1 [[CMP_2]], label %loop_header.preheader, label %main.pseudo.exit
; CHECK: range_check_block: ; preds = %inner_loop
; CHECK-NEXT: %range_check = icmp slt i32 %iv, %n
; CHECK-NEXT: br i1 true, label %loop_latch, label %deopt.loopexit2
; CHECK: loop_latch: ; preds = %range_check_block
; CHECK-NEXT: %iv_next = add i32 %iv, 1
; CHECK-NEXT: %loop_cond = icmp ult i32 %iv_next, 400
; CHECK-NEXT: [[COND:%[^ ]+]] = icmp ult i32 %iv_next, %exit.mainloop.at
; CHECK-NEXT: br i1 [[COND]], label %loop_header, label %main.exit.selector
; CHECK: main.exit.selector: ; preds = %loop_latch
; CHECK-NEXT: %iv_next.lcssa = phi i32 [ %iv_next, %loop_latch ]
; CHECK-NEXT: %iv.lcssa = phi i32 [ %iv, %loop_latch ]
; CHECK-NEXT: [[MES_COND:%[^ ]+]] = icmp ult i32 %iv_next.lcssa, 400
; CHECK-NEXT: br i1 [[MES_COND]], label %main.pseudo.exit, label %exit
; CHECK: loop_latch.postloop: ; preds = %range_check_block.postloop
; CHECK-NEXT: %iv_next.postloop = add i32 %iv.postloop, 1
; CHECK-NEXT: %loop_cond.postloop = icmp ult i32 %iv_next.postloop, 400
; CHECK-NEXT: br i1 %loop_cond.postloop, label %loop_header.postloop, label %exit.loopexit
entry:
%n = load i32, i32* %p, !range !0
br label %loop_header
loop_header: ; preds = %loop_latch, %entry
%iv = phi i32 [ 2, %entry ], [ %iv_next, %loop_latch ]
%iv.prev = phi i32 [ 1, %entry ], [ %iv, %loop_latch ]
%tmp2 = icmp sgt i32 %iv.prev, -1
br i1 %tmp2, label %loop_header.split.us, label %exit
loop_header.split.us: ; preds = %loop_header
br label %inner_loop
inner_loop: ; preds = %inner_loop, %loop_header.split.us
%inner_iv = phi i32 [ 1, %loop_header.split.us ], [ %inner_iv_next, %inner_loop ]
%inner_iv_next = add nuw nsw i32 %inner_iv, 1
%inner_cond = icmp ult i32 %inner_iv_next, 31
br i1 %inner_cond, label %inner_loop, label %range_check_block
exit: ; preds = %loop_latch, %loop_header
ret void
range_check_block: ; preds = %inner_loop
%range_check = icmp slt i32 %iv, %n
br i1 %range_check, label %loop_latch, label %deopt
loop_latch: ; preds = %range_check_block
%iv_next = add i32 %iv, 1
%loop_cond = icmp ult i32 %iv_next, 400
br i1 %loop_cond, label %loop_header, label %exit
deopt: ; preds = %range_check_block
ret void
}
!0 = !{i32 0, i32 50}