d1e880acaa
Currently, we hardly ever actually run SCEV verification, even in tests with -verify-scev. This is because the NewPM LPM does not verify SCEV. The reason for this is that SCEV verification can actually change the result of subsequent SCEV queries, which means that you see different transformations depending on whether verification is enabled or not. To allow verification in the LPM, this limits verification to BECounts that have actually been cached. It will not calculate new BECounts. BackedgeTakenInfo::getExact() is still not entirely readonly, it still calls getUMinFromMismatchedTypes(). But I hope that this is not problematic in the same way. (This could be avoided by performing the umin in the other SCEV instance, but this would require duplicating some of the code.) Differential Revision: https://reviews.llvm.org/D120551
34 lines
799 B
LLVM
34 lines
799 B
LLVM
; RUN: opt -indvars -S < %s | FileCheck %s
|
|
|
|
; Check that IndVarSimplify's result is not influenced by stray calls to
|
|
; ScalarEvolution in debug builds. However, -verify-indvars may still do
|
|
; such calls.
|
|
; llvm.org/PR44815
|
|
|
|
; In this test, adding -verify-indvars causes %tmp13 to not be optimized away.
|
|
; CHECK-LABEL: @foo
|
|
; CHECK-NOT: phi i32
|
|
|
|
target triple = "x86_64-unknown-linux-gnu"
|
|
|
|
@b = external dso_local local_unnamed_addr global i32
|
|
|
|
define dso_local void @foo() {
|
|
tmp0:
|
|
br label %tmp12
|
|
|
|
tmp7:
|
|
%tmp8 = add nuw nsw i32 %tmp13, 1
|
|
store i32 undef, i32* @b
|
|
br label %tmp12
|
|
|
|
tmp12:
|
|
%tmp13 = phi i32 [ 2, %tmp0 ], [ %tmp8, %tmp7 ]
|
|
%tmp14 = phi i32 [ 1, %tmp0 ], [ %tmp13, %tmp7 ]
|
|
%tmp15 = icmp ult i32 %tmp14, undef
|
|
br i1 %tmp15, label %tmp7, label %tmp16
|
|
|
|
tmp16:
|
|
ret void
|
|
}
|