[llvm] [LAA] Rewrite findForkedPointer, fixing freeze (PR #140298)

[Florian Hahn via llvm-commits]

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@@ -16,8 +16,10 @@ define void @test1_select_invariant(ptr %src.1, ptr %src.2, ptr %dst, i1 %c, i8
 ; CHECK-NEXT:    [[TMP5:%.*]] = add nuw nsw i64 [[TMP4]], 1
 ; CHECK-NEXT:    [[UGLYGEP:%.*]] = getelementptr i8, ptr [[DST:%.*]], i64 [[TMP5]]
 ; CHECK-NEXT:    [[UGLYGEP1:%.*]] = getelementptr i8, ptr [[PTR_SEL]], i64 1
-; CHECK-NEXT:    [[BOUND0:%.*]] = icmp ult ptr [[DST]], [[UGLYGEP1]]
-; CHECK-NEXT:    [[BOUND1:%.*]] = icmp ult ptr [[PTR_SEL]], [[UGLYGEP]]
+; CHECK-NEXT:    [[PTR_SEL_FR:%.*]] = freeze ptr [[PTR_SEL]]
+; CHECK-NEXT:    [[SCEVGEP1_FR:%.*]] = freeze ptr [[UGLYGEP1]]
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fhahn wrote:

Are those freeze's needed? PTR_SEL is guaranteed to be dereferenced in the loop, so cannot be poison

https://github.com/llvm/llvm-project/pull/140298