[llvm] [SimplfyCFG] Set `MD_prof` for `select` used for certain conditional simplifications (PR #154426)

[David Li via llvm-commits]

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@@ -557,9 +557,9 @@ return:
 define i32 @SimplifyCondBranchToCondBranch(i1 %cmpa, i1 %cmpb) {
 ; CHECK-LABEL: @SimplifyCondBranchToCondBranch(
 ; CHECK-NEXT:  block1:
-; CHECK-NEXT:    [[BRMERGE:%.*]] = select i1 [[CMPA:%.*]], i1 true, i1 [[CMPB:%.*]]
-; CHECK-NEXT:    [[DOTMUX:%.*]] = select i1 [[CMPA]], i32 0, i32 2, !prof [[PROF13:![0-9]+]]
-; CHECK-NEXT:    [[OUTVAL:%.*]] = select i1 [[BRMERGE]], i32 [[DOTMUX]], i32 1, !prof [[PROF14:![0-9]+]]
+; CHECK-NEXT:    [[BRMERGE:%.*]] = select i1 [[CMPA:%.*]], i1 true, i1 [[CMPB:%.*]], !prof [[PROF13:![0-9]+]]
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david-xl wrote:

two selects in the same block with the same condition should have identical prof data to be consisitent.

https://github.com/llvm/llvm-project/pull/154426