[llvm] [InstCombine] Replace all dominated uses of condition with constants (PR #105510)

[Yingwei Zheng via llvm-commits]

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@@ -1664,11 +1664,9 @@ define i64 @pr92084(double %x) {
 ; CHECK-NEXT:    [[CMP:%.*]] = fcmp uno double [[X:%.*]], 0.000000e+00
 ; CHECK-NEXT:    br i1 [[CMP]], label [[IF_THEN1:%.*]], label [[IF_ELSE:%.*]]
 ; CHECK:       if.then1:
-; CHECK-NEXT:    br i1 [[CMP]], label [[IF_ELSE]], label [[IF_THEN2:%.*]]
+; CHECK-NEXT:    br i1 true, label [[IF_ELSE]], label [[IF_THEN2:%.*]]
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dtcxzyw wrote:

> Need to use independent condition for the second branch.

No. The original issue only reproduces with effectively unreachable uses of `%x`. Using an independent condition for the second branch will break this.


https://github.com/llvm/llvm-project/pull/105510