forked from OSchip/llvm-project
59 lines
1.3 KiB
LLVM
59 lines
1.3 KiB
LLVM
|
; RUN: opt -jump-threading -S %s | FileCheck %s
|
||
|
|
|
||
|
|
; Check that we thread arg2neg -> checkpos -> end.
|
||
|
|
;
|
||
|
|
; LazyValueInfo would previously fail to analyze the value of %arg in arg2neg
|
||
|
|
; because its predecessing blocks (checkneg) hadn't been processed yet (PR21238)
|
||
|
|
|
||
|
|
; CHECK-LABEL: @test_jump_threading
|
||
|
|
; CHECK: arg2neg:
|
||
|
|
; CHECK-NEXT: br i1 %arg1, label %end, label %checkpos.thread
|
||
|
|
; CHECK: checkpos.thread:
|
||
|
|
; CHECK-NEXT: br label %end
|
||
|
|
|
||
|
|
define i32 @test_jump_threading(i1 %arg1, i32 %arg2) {
|
||
|
|
checkneg:
|
||
|
|
%cmp = icmp slt i32 %arg2, 0
|
||
|
|
br i1 %cmp, label %arg2neg, label %checkpos
|
||
|
|
|
||
|
|
arg2neg:
|
||
|
|
br i1 %arg1, label %end, label %checkpos
|
||
|
|
|
||
|
|
checkpos:
|
||
|
|
%cmp2 = icmp sgt i32 %arg2, 0
|
||
|
|
br i1 %cmp2, label %arg2pos, label %end
|
||
|
|
|
||
|
|
arg2pos:
|
||
|
|
br label %end
|
||
|
|
|
||
|
|
end:
|
||
|
|
%0 = phi i32 [ 1, %arg2neg ], [ 2, %checkpos ], [ 3, %arg2pos ]
|
||
|
|
ret i32 %0
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
; arg2neg has an edge back to itself. If LazyValueInfo is not careful when
|
||
|
|
; visiting predecessors, it could get into an infinite loop.
|
||
|
|
|
||
|
|
; CHECK-LABEL: test_infinite_loop
|
||
|
|
|
||
|
|
define i32 @test_infinite_loop(i1 %arg1, i32 %arg2) {
|
||
|
|
checkneg:
|
||
|
|
%cmp = icmp slt i32 %arg2, 0
|
||
|
|
br i1 %cmp, label %arg2neg, label %checkpos
|
||
|
|
|
||
|
|
arg2neg:
|
||
|
|
br i1 %arg1, label %arg2neg, label %checkpos
|
||
|
|
|
||
|
|
checkpos:
|
||
|
|
%cmp2 = icmp sgt i32 %arg2, 0
|
||
|
|
br i1 %cmp2, label %arg2pos, label %end
|
||
|
|
|
||
|
|
arg2pos:
|
||
|
|
br label %end
|
||
|
|
|
||
|
|
end:
|
||
|
|
%0 = phi i32 [ 2, %checkpos ], [ 3, %arg2pos ]
|
||
|
|
ret i32 %0
|
||
|
|
}
|