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

[Nikita Popov via llvm-commits]

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@@ -11,14 +11,12 @@ define void @phi_recurrence_start_first() {
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    br label [[WHILE_COND:%.*]]
 ; CHECK:       while.cond:
-; CHECK-NEXT:    [[CELL_0:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[START:%.*]], [[FOR_COND26:%.*]] ]
 ; CHECK-NEXT:    [[COND_V:%.*]] = call i1 @cond()
 ; CHECK-NEXT:    br i1 [[COND_V]], label [[IF_THEN:%.*]], label [[WHILE_END:%.*]]
 ; CHECK:       if.then:
-; CHECK-NEXT:    [[START]] = add nuw nsw i32 [[CELL_0]], 1
-; CHECK-NEXT:    br i1 [[COND_V]], label [[FOR_COND11:%.*]], label [[FOR_COND26]]
+; CHECK-NEXT:    br i1 true, label [[FOR_COND11:%.*]], label [[FOR_COND26:%.*]]
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nikic wrote:

Same here and probably some other tests.

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