[llvm] [polly] [SimpleLoopUnswitch] Don't use BlockFrequencyInfo to skip cold loops (PR #159522)

[Teresa Johnson via llvm-commits]

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@@ -17,7 +18,7 @@
 
 define void @_Z11hotFunctionbiiPiS_S_(i1 %cond, i32 %M, i32 %N, ptr %A, ptr %B, ptr %C) !prof !36 {
 ; CHECK-LABEL: define void @_Z11hotFunctionbiiPiS_S_
-; CHECK-SAME: (i1 [[COND:%.*]], i32 [[M:%.*]], i32 [[N:%.*]], ptr [[A:%.*]], ptr [[B:%.*]], ptr [[C:%.*]]) !prof [[PROF16:![0-9]+]] {
+; CHECK-SAME: (i1 [[COND:%.*]], i32 [[M:%.*]], i32 [[N:%.*]], ptr [[A:%.*]], ptr [[B:%.*]], ptr [[C:%.*]]) #[[ATTR0:[0-9]+]] {{.*}}{
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teresajohnson wrote:

ATTR0 is never matched with anything later on - what is this trying to check? I'm a little unsure of what changed here as per the comments and the function name this is a cold loop nest in a hot function, so shouldn't we stop seeing it be unswitched with this PR?

https://github.com/llvm/llvm-project/pull/159522