forked from OSchip/llvm-project
80 lines
2.1 KiB
LLVM
80 lines
2.1 KiB
LLVM
|
; RUN: opt < %s -S -basicaa -licm | FileCheck %s
|
||
|
|
||
|
; Check that we can hoist unordered loads
|
||
|
define i32 @test1(i32* nocapture %y) nounwind uwtable ssp {
|
||
|
entry:
|
||
|
br label %loop
|
||
|
|
||
|
loop:
|
||
|
%i = phi i32 [ %inc, %loop ], [ 0, %entry ]
|
||
|
%val = load atomic i32* %y unordered, align 4
|
||
|
%inc = add nsw i32 %i, 1
|
||
|
%exitcond = icmp eq i32 %inc, %val
|
||
|
br i1 %exitcond, label %end, label %loop
|
||
|
|
||
|
end:
|
||
|
ret i32 %val
|
||
|
; CHECK: define i32 @test1(
|
||
|
; CHECK: load atomic
|
||
|
; CHECK-NEXT: br label %loop
|
||
|
}
|
||
|
|
||
|
; Check that we don't sink/hoist monotonic loads
|
||
|
; (Strictly speaking, it's not forbidden, but it's supposed to be possible to
|
||
|
; use monotonic for spinlock-like constructs.)
|
||
|
define i32 @test2(i32* nocapture %y) nounwind uwtable ssp {
|
||
|
entry:
|
||
|
br label %loop
|
||
|
|
||
|
loop:
|
||
|
%val = load atomic i32* %y monotonic, align 4
|
||
|
%exitcond = icmp ne i32 %val, 0
|
||
|
br i1 %exitcond, label %end, label %loop
|
||
|
|
||
|
end:
|
||
|
ret i32 %val
|
||
|
; CHECK: define i32 @test2(
|
||
|
; CHECK: load atomic
|
||
|
; CHECK-NEXT: %exitcond = icmp ne
|
||
|
; CHECK-NEXT: br i1 %exitcond, label %end, label %loop
|
||
|
}
|
||
|
|
||
|
; Check that we hoist unordered around monotonic.
|
||
|
; (The noalias shouldn't be necessary in theory, but LICM isn't quite that
|
||
|
; smart yet.)
|
||
|
define i32 @test3(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
|
||
|
entry:
|
||
|
br label %loop
|
||
|
|
||
|
loop:
|
||
|
%vala = load atomic i32* %y monotonic, align 4
|
||
|
%valb = load atomic i32* %x unordered, align 4
|
||
|
%exitcond = icmp ne i32 %vala, %valb
|
||
|
br i1 %exitcond, label %end, label %loop
|
||
|
|
||
|
end:
|
||
|
ret i32 %vala
|
||
|
; CHECK: define i32 @test3(
|
||
|
; CHECK: load atomic i32* %x unordered
|
||
|
; CHECK-NEXT: br label %loop
|
||
|
}
|
||
|
|
||
|
; Don't try to "sink" unordered stores yet; it is legal, but the machinery
|
||
|
; isn't there.
|
||
|
define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
|
||
|
entry:
|
||
|
br label %loop
|
||
|
|
||
|
loop:
|
||
|
%vala = load atomic i32* %y monotonic, align 4
|
||
|
store atomic i32 %vala, i32* %x unordered, align 4
|
||
|
%exitcond = icmp ne i32 %vala, 0
|
||
|
br i1 %exitcond, label %end, label %loop
|
||
|
|
||
|
end:
|
||
|
ret i32 %vala
|
||
|
; CHECK: define i32 @test4(
|
||
|
; CHECK: load atomic i32* %y monotonic
|
||
|
; CHECK-NEXT: store atomic
|
||
|
}
|