llvm/test/Transforms/SimplifyCFG/PhiEliminate.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; Test a bunch of cases where the cfg simplification code should
; be able to fold PHI nodes into computation in common cases.  Folding the PHI
; nodes away allows the branches to be eliminated, performing a simple form of
; 'if conversion'.

; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S | FileCheck %s

declare void @use(i1)

declare void @use.upgrd.1(i32)


define void @test(i1 %c, i32 %V, i32 %V2) {
; <label>:0
; CHECK-LABEL: @test(
; CHECK-NEXT:  F:
; CHECK-NEXT:    [[SPEC_SELECT:%.*]] = select i1 [[C:%.*]], i1 false, i1 true
; CHECK-NEXT:    [[SPEC_SELECT1:%.*]] = select i1 [[C]], i32 0, i32 [[V:%.*]]
; CHECK-NEXT:    call void @use(i1 [[SPEC_SELECT]])
; CHECK-NEXT:    call void @use.upgrd.1(i32 [[SPEC_SELECT1]])
; CHECK-NEXT:    ret void
;
  br i1 %c, label %T, label %F
T:              ; preds = %0
  br label %F
F:              ; preds = %T, %0
  %B1 = phi i1 [ true, %0 ], [ false, %T ]                ; <i1> [#uses=1]
  %I6 = phi i32 [ %V, %0 ], [ 0, %T ]             ; <i32> [#uses=1]
  call void @use( i1 %B1 )
  call void @use.upgrd.1( i32 %I6 )
  ret void
}