atomics.ll
6.37 KB
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; RUN: opt < %s -S -basic-aa -licm -enable-mssa-loop-dependency=false -enable-new-pm=0 | FileCheck -check-prefixes=CHECK,AST %s
; RUN: opt < %s -S -basic-aa -licm -enable-mssa-loop-dependency=true -enable-new-pm=0 | FileCheck -check-prefixes=CHECK,MSSA %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<opt-remark-emit>,loop(licm)' < %s -S | FileCheck -check-prefixes=CHECK,AST %s
; RUN: opt -aa-pipeline=basic-aa -passes='require<opt-remark-emit>,loop-mssa(licm)' < %s -S | FileCheck -check-prefixes=CHECK,MSSA %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, 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-LABEL: 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, i32* %y monotonic, align 4
%exitcond = icmp ne i32 %val, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %val
; CHECK-LABEL: 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, i32* %y monotonic, align 4
%valb = load atomic i32, i32* %x unordered, align 4
%exitcond = icmp ne i32 %vala, %valb
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test3(
; CHECK: load atomic i32, i32* %x unordered
; CHECK-NEXT: br label %loop
}
; We can sink an unordered store
define i32 @test4(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
entry:
br label %loop
loop:
%vala = load atomic i32, 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-LABEL: define i32 @test4(
; CHECK-LABEL: loop:
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NOT: store
; CHECK-LABEL: end:
; CHECK-NEXT: %[[LCSSAPHI:.*]] = phi i32 [ %vala
; CHECK: store atomic i32 %[[LCSSAPHI]], i32* %x unordered, align 4
}
; We currently don't handle ordered atomics.
define i32 @test5(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
entry:
br label %loop
loop:
%vala = load atomic i32, i32* %y monotonic, align 4
store atomic i32 %vala, i32* %x release, align 4
%exitcond = icmp ne i32 %vala, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test5(
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NEXT: store atomic
}
; We currently don't touch volatiles
define i32 @test6(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
entry:
br label %loop
loop:
%vala = load atomic i32, i32* %y monotonic, align 4
store volatile i32 %vala, i32* %x, align 4
%exitcond = icmp ne i32 %vala, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test6(
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NEXT: store volatile
}
; We currently don't touch volatiles
define i32 @test6b(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
entry:
br label %loop
loop:
%vala = load atomic i32, i32* %y monotonic, align 4
store atomic volatile 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-LABEL: define i32 @test6b(
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NEXT: store atomic volatile
}
; Mixing unorder atomics and normal loads/stores is
; current unimplemented
define i32 @test7(i32* nocapture noalias %x, i32* nocapture %y) nounwind uwtable ssp {
entry:
br label %loop
loop:
store i32 5, i32* %x
%vala = load atomic i32, 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-LABEL: define i32 @test7(
; CHECK: store i32 5, i32* %x
; CHECK-NEXT: load atomic i32, i32* %y
; CHECK-NEXT: store atomic i32
}
; Three provably noalias locations - we can sink normal and unordered, but
; not monotonic
define i32 @test7b(i32* nocapture noalias %x, i32* nocapture %y, i32* noalias nocapture %z) nounwind uwtable ssp {
entry:
br label %loop
loop:
store i32 5, i32* %x
%vala = load atomic i32, i32* %y monotonic, align 4
store atomic i32 %vala, i32* %z unordered, align 4
%exitcond = icmp ne i32 %vala, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test7b(
; AST-LABEL: entry:
; AST: store i32 5, i32* %x
; CHECK-LABEL: loop:
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-LABEL: end:
; MSSA: store i32 5, i32* %x
; CHECK: store atomic i32 %{{.+}}, i32* %z unordered, align 4
}
define i32 @test8(i32* nocapture noalias %x, i32* nocapture %y) {
entry:
br label %loop
loop:
%vala = load atomic i32, i32* %y monotonic, align 4
store atomic i32 %vala, i32* %x unordered, align 4
fence release
%exitcond = icmp ne i32 %vala, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test8(
; CHECK-LABEL: loop:
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NEXT: store atomic
; CHECK-NEXT: fence
}
; Exact semantics of monotonic accesses are a bit vague in the C++ spec,
; for the moment, be conservative and don't touch them.
define i32 @test9(i32* nocapture noalias %x, i32* nocapture %y) {
entry:
br label %loop
loop:
%vala = load atomic i32, i32* %y monotonic, align 4
store atomic i32 %vala, i32* %x monotonic, align 4
%exitcond = icmp ne i32 %vala, 0
br i1 %exitcond, label %end, label %loop
end:
ret i32 %vala
; CHECK-LABEL: define i32 @test9(
; CHECK-LABEL: loop:
; CHECK: load atomic i32, i32* %y monotonic
; CHECK-NEXT: store atomic i32 %vala, i32* %x monotonic, align 4
}