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; RUN: opt < %s -licm -S | FileCheck %s
@X = global i32 7 ; <i32*> [#uses=4]
define void @test1(i32 %i) {
Entry:
br label %Loop
; CHECK: @test1
; CHECK: Entry:
; CHECK-NEXT: load i32* @X
; CHECK-NEXT: br label %Loop
Loop: ; preds = %Loop, %0
%j = phi i32 [ 0, %Entry ], [ %Next, %Loop ] ; <i32> [#uses=1]
%x = load i32* @X ; <i32> [#uses=1]
%x2 = add i32 %x, 1 ; <i32> [#uses=1]
store i32 %x2, i32* @X
%Next = add i32 %j, 1 ; <i32> [#uses=2]
%cond = icmp eq i32 %Next, 0 ; <i1> [#uses=1]
br i1 %cond, label %Out, label %Loop
Out:
ret void
; CHECK: Out:
; CHECK-NEXT: store i32 %x2, i32* @X
; CHECK-NEXT: ret void
}
define void @test2(i32 %i) {
Entry:
br label %Loop
; CHECK: @test2
; CHECK: Entry:
; CHECK-NEXT: %X1 = getelementptr i32* @X, i64 0
; CHECK-NEXT: %X2 = getelementptr i32* @X, i64 0
; CHECK-NEXT: %X1.promoted = load i32* %X1
; CHECK-NEXT: br label %Loop
Loop: ; preds = %Loop, %0
%X1 = getelementptr i32* @X, i64 0 ; <i32*> [#uses=1]
%A = load i32* %X1 ; <i32> [#uses=1]
%V = add i32 %A, 1 ; <i32> [#uses=1]
%X2 = getelementptr i32* @X, i64 0 ; <i32*> [#uses=1]
store i32 %V, i32* %X2
br i1 false, label %Loop, label %Exit
Exit: ; preds = %Loop
ret void
; CHECK: Exit:
; CHECK-NEXT: store i32 %V, i32* %X1
; CHECK-NEXT: ret void
}
define void @test3(i32 %i) {
; CHECK: @test3
br label %Loop
Loop:
; Should not promote this to a register
%x = volatile load i32* @X
%x2 = add i32 %x, 1
store i32 %x2, i32* @X
br i1 true, label %Out, label %Loop
; CHECK: Loop:
; CHECK-NEXT: volatile load
Out: ; preds = %Loop
ret void
}
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