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; RUN: opt -S -early-cse < %s | FileCheck %s
; RUN: opt -S -basicaa -early-cse-memssa < %s | FileCheck %s
declare void @clobber_and_use(i32)
define void @f_0(i32* %ptr) {
; CHECK-LABEL: @f_0(
; CHECK: %val0 = load i32, i32* %ptr, !invariant.load !0
; CHECK: call void @clobber_and_use(i32 %val0)
; CHECK: call void @clobber_and_use(i32 %val0)
; CHECK: call void @clobber_and_use(i32 %val0)
; CHECK: ret void
%val0 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val0)
%val1 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val1)
%val2 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val2)
ret void
}
define void @f_1(i32* %ptr) {
; We can forward invariant loads to non-invariant loads.
; CHECK-LABEL: @f_1(
; CHECK: %val0 = load i32, i32* %ptr, !invariant.load !0
; CHECK: call void @clobber_and_use(i32 %val0)
; CHECK: call void @clobber_and_use(i32 %val0)
%val0 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val0)
%val1 = load i32, i32* %ptr
call void @clobber_and_use(i32 %val1)
ret void
}
define void @f_2(i32* %ptr) {
; We can forward a non-invariant load into an invariant load.
; CHECK-LABEL: @f_2(
; CHECK: %val0 = load i32, i32* %ptr
; CHECK: call void @clobber_and_use(i32 %val0)
; CHECK: call void @clobber_and_use(i32 %val0)
%val0 = load i32, i32* %ptr
call void @clobber_and_use(i32 %val0)
%val1 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val1)
ret void
}
define void @f_3(i1 %cond, i32* %ptr) {
; CHECK-LABEL: @f_3(
%val0 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val0)
br i1 %cond, label %left, label %right
; CHECK: %val0 = load i32, i32* %ptr, !invariant.load !0
; CHECK: left:
; CHECK-NEXT: call void @clobber_and_use(i32 %val0)
left:
%val1 = load i32, i32* %ptr
call void @clobber_and_use(i32 %val1)
ret void
right:
ret void
}
define void @f_4(i1 %cond, i32* %ptr) {
; Negative test -- can't forward %val0 to %va1 because that'll break
; def-dominates-use.
; CHECK-LABEL: @f_4(
br i1 %cond, label %left, label %merge
left:
; CHECK: left:
; CHECK-NEXT: %val0 = load i32, i32* %ptr, !invariant.load !
; CHECK-NEXT: call void @clobber_and_use(i32 %val0)
%val0 = load i32, i32* %ptr, !invariant.load !{}
call void @clobber_and_use(i32 %val0)
br label %merge
merge:
; CHECK: merge:
; CHECK-NEXT: %val1 = load i32, i32* %ptr
; CHECK-NEXT: call void @clobber_and_use(i32 %val1)
%val1 = load i32, i32* %ptr
call void @clobber_and_use(i32 %val1)
ret void
}
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