504 lines
13 KiB
LLVM
504 lines
13 KiB
LLVM
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; RUN: opt -basic-aa -gvn -S < %s | FileCheck %s
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target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
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target triple = "x86_64-apple-macosx10.7.0"
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@x = common global i32 0, align 4
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@y = common global i32 0, align 4
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; GVN across unordered store (allowed)
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define i32 @test1() nounwind uwtable ssp {
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; CHECK-LABEL: test1
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; CHECK: add i32 %x, %x
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entry:
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%x = load i32, i32* @y
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store atomic i32 %x, i32* @x unordered, align 4
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%y = load i32, i32* @y
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%z = add i32 %x, %y
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ret i32 %z
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}
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; GVN across unordered load (allowed)
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define i32 @test3() nounwind uwtable ssp {
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; CHECK-LABEL: test3
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; CHECK: add i32 %x, %x
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entry:
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%x = load i32, i32* @y
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%y = load atomic i32, i32* @x unordered, align 4
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%z = load i32, i32* @y
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%a = add i32 %x, %z
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%b = add i32 %y, %a
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ret i32 %b
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}
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; GVN load to unordered load (allowed)
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define i32 @test5() nounwind uwtable ssp {
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; CHECK-LABEL: test5
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; CHECK: add i32 %x, %x
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entry:
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%x = load atomic i32, i32* @x unordered, align 4
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%y = load i32, i32* @x
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%z = add i32 %x, %y
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ret i32 %z
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}
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; GVN unordered load to load (unordered load must not be removed)
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define i32 @test6() nounwind uwtable ssp {
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; CHECK-LABEL: test6
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; CHECK: load atomic i32, i32* @x unordered
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entry:
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%x = load i32, i32* @x
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%x2 = load atomic i32, i32* @x unordered, align 4
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%x3 = add i32 %x, %x2
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ret i32 %x3
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}
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; GVN across release-acquire pair (forbidden)
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define i32 @test7() nounwind uwtable ssp {
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; CHECK-LABEL: test7
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; CHECK: add i32 %x, %y
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entry:
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%x = load i32, i32* @y
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store atomic i32 %x, i32* @x release, align 4
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%w = load atomic i32, i32* @x acquire, align 4
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%y = load i32, i32* @y
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%z = add i32 %x, %y
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ret i32 %z
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}
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; GVN across monotonic store (allowed)
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define i32 @test9() nounwind uwtable ssp {
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; CHECK-LABEL: test9
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; CHECK: add i32 %x, %x
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entry:
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%x = load i32, i32* @y
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store atomic i32 %x, i32* @x monotonic, align 4
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%y = load i32, i32* @y
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%z = add i32 %x, %y
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ret i32 %z
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}
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; GVN of an unordered across monotonic load (not allowed)
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define i32 @test10() nounwind uwtable ssp {
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; CHECK-LABEL: test10
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; CHECK: add i32 %x, %y
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entry:
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%x = load atomic i32, i32* @y unordered, align 4
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%clobber = load atomic i32, i32* @x monotonic, align 4
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%y = load atomic i32, i32* @y monotonic, align 4
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%z = add i32 %x, %y
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ret i32 %z
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}
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define i32 @PR22708(i1 %flag) {
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; CHECK-LABEL: PR22708
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entry:
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br i1 %flag, label %if.then, label %if.end
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if.then:
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store i32 43, i32* @y, align 4
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; CHECK: store i32 43, i32* @y, align 4
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br label %if.end
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if.end:
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load atomic i32, i32* @x acquire, align 4
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%load = load i32, i32* @y, align 4
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; CHECK: load atomic i32, i32* @x acquire, align 4
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; CHECK: load i32, i32* @y, align 4
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ret i32 %load
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}
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; CHECK-LABEL: @test12(
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; Can't remove a load over a ordering barrier
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define i32 @test12(i1 %B, i32* %P1, i32* %P2) {
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%load0 = load i32, i32* %P1
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%1 = load atomic i32, i32* %P2 seq_cst, align 4
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%load1 = load i32, i32* %P1
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%sel = select i1 %B, i32 %load0, i32 %load1
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ret i32 %sel
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; CHECK: load i32, i32* %P1
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; CHECK: load i32, i32* %P1
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}
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; CHECK-LABEL: @test13(
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; atomic to non-atomic forwarding is legal
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define i32 @test13(i32* %P1) {
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%a = load atomic i32, i32* %P1 seq_cst, align 4
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%b = load i32, i32* %P1
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK: load atomic i32, i32* %P1
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; CHECK: ret i32 0
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}
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; CHECK-LABEL: @test13b(
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define i32 @test13b(i32* %P1) {
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store atomic i32 0, i32* %P1 unordered, align 4
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%b = load i32, i32* %P1
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ret i32 %b
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; CHECK: ret i32 0
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}
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; CHECK-LABEL: @test14(
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; atomic to unordered atomic forwarding is legal
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define i32 @test14(i32* %P1) {
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%a = load atomic i32, i32* %P1 seq_cst, align 4
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%b = load atomic i32, i32* %P1 unordered, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK: load atomic i32, i32* %P1 seq_cst
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; CHECK-NEXT: ret i32 0
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}
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; CHECK-LABEL: @test15(
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; implementation restriction: can't forward to stonger
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; than unordered
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define i32 @test15(i32* %P1, i32* %P2) {
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%a = load atomic i32, i32* %P1 seq_cst, align 4
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%b = load atomic i32, i32* %P1 seq_cst, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK: load atomic i32, i32* %P1
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; CHECK: load atomic i32, i32* %P1
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}
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; CHECK-LABEL: @test16(
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; forwarding non-atomic to atomic is wrong! (However,
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; it would be legal to use the later value in place of the
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; former in this particular example. We just don't
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; do that right now.)
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define i32 @test16(i32* %P1, i32* %P2) {
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%a = load i32, i32* %P1, align 4
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%b = load atomic i32, i32* %P1 unordered, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK: load i32, i32* %P1
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; CHECK: load atomic i32, i32* %P1
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}
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; CHECK-LABEL: @test16b(
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define i32 @test16b(i32* %P1) {
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store i32 0, i32* %P1
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%b = load atomic i32, i32* %P1 unordered, align 4
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ret i32 %b
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; CHECK: load atomic i32, i32* %P1
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}
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; Can't DSE across a full fence
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define void @fence_seq_cst_store(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @fence_seq_cst_store(
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; CHECK: store
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; CHECK: store atomic
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; CHECK: store
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store i32 0, i32* %P1, align 4
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store atomic i32 0, i32* %P2 seq_cst, align 4
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store i32 0, i32* %P1, align 4
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ret void
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}
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; Can't DSE across a full fence
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define void @fence_seq_cst(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @fence_seq_cst(
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; CHECK: store
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; CHECK: fence seq_cst
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; CHECK: store
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store i32 0, i32* %P1, align 4
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fence seq_cst
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store i32 0, i32* %P1, align 4
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ret void
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}
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; Can't DSE across a full syncscope("singlethread") fence
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define void @fence_seq_cst_st(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @fence_seq_cst_st(
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; CHECK: store
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; CHECK: fence syncscope("singlethread") seq_cst
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; CHECK: store
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store i32 0, i32* %P1, align 4
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fence syncscope("singlethread") seq_cst
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store i32 0, i32* %P1, align 4
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ret void
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}
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; Can't DSE across a full fence
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define void @fence_asm_sideeffect(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @fence_asm_sideeffect(
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; CHECK: store
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; CHECK: call void asm sideeffect
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; CHECK: store
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store i32 0, i32* %P1, align 4
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call void asm sideeffect "", ""()
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store i32 0, i32* %P1, align 4
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ret void
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}
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; Can't DSE across a full fence
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define void @fence_asm_memory(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @fence_asm_memory(
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; CHECK: store
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; CHECK: call void asm
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; CHECK: store
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store i32 0, i32* %P1, align 4
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call void asm "", "~{memory}"()
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store i32 0, i32* %P1, align 4
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ret void
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}
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; Can't remove a volatile load
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define i32 @volatile_load(i32* %P1, i32* %P2) {
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%a = load i32, i32* %P1, align 4
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%b = load volatile i32, i32* %P1, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK-LABEL: @volatile_load(
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; CHECK: load i32, i32* %P1
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; CHECK: load volatile i32, i32* %P1
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}
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; Can't remove redundant volatile loads
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define i32 @redundant_volatile_load(i32* %P1, i32* %P2) {
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%a = load volatile i32, i32* %P1, align 4
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%b = load volatile i32, i32* %P1, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK-LABEL: @redundant_volatile_load(
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; CHECK: load volatile i32, i32* %P1
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; CHECK: load volatile i32, i32* %P1
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; CHECK: sub
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}
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; Can't DSE a volatile store
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define void @volatile_store(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @volatile_store(
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; CHECK: store volatile
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; CHECK: store
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store volatile i32 0, i32* %P1, align 4
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store i32 3, i32* %P1, align 4
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ret void
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}
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; Can't DSE a redundant volatile store
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define void @redundant_volatile_store(i32* %P1, i32* %P2) {
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; CHECK-LABEL: @redundant_volatile_store(
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; CHECK: store volatile
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; CHECK: store volatile
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store volatile i32 0, i32* %P1, align 4
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store volatile i32 0, i32* %P1, align 4
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ret void
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}
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; Can value forward from volatiles
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define i32 @test20(i32* %P1, i32* %P2) {
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%a = load volatile i32, i32* %P1, align 4
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%b = load i32, i32* %P1, align 4
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%res = sub i32 %a, %b
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ret i32 %res
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; CHECK-LABEL: @test20(
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; CHECK: load volatile i32, i32* %P1
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; CHECK: ret i32 0
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}
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; We're currently conservative about widening
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define i64 @widen1(i32* %P1) {
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; CHECK-LABEL: @widen1(
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; CHECK: load atomic i32, i32* %P1
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; CHECK: load atomic i64, i64* %p2
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%p2 = bitcast i32* %P1 to i64*
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%a = load atomic i32, i32* %P1 unordered, align 4
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%b = load atomic i64, i64* %p2 unordered, align 4
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%a64 = sext i32 %a to i64
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%res = sub i64 %a64, %b
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ret i64 %res
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}
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; narrowing does work
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define i64 @narrow(i32* %P1) {
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; CHECK-LABEL: @narrow(
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; CHECK: load atomic i64, i64* %p2
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; CHECK-NOT: load atomic i32, i32* %P1
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%p2 = bitcast i32* %P1 to i64*
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%a64 = load atomic i64, i64* %p2 unordered, align 4
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%b = load atomic i32, i32* %P1 unordered, align 4
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%b64 = sext i32 %b to i64
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%res = sub i64 %a64, %b64
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ret i64 %res
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}
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; Missed optimization, we don't yet optimize ordered loads
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define i64 @narrow2(i32* %P1) {
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; CHECK-LABEL: @narrow2(
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; CHECK: load atomic i64, i64* %p2
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; CHECK: load atomic i32, i32* %P1
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%p2 = bitcast i32* %P1 to i64*
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%a64 = load atomic i64, i64* %p2 acquire, align 4
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%b = load atomic i32, i32* %P1 acquire, align 4
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%b64 = sext i32 %b to i64
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%res = sub i64 %a64, %b64
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ret i64 %res
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}
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; Note: The cross block FRE testing is deliberately light. All of the tricky
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|
|
; bits of legality are shared code with the block-local FRE above. These
|
||
|
|
; are here only to show that we haven't obviously broken anything.
|
||
|
|
|
||
|
|
; unordered atomic to unordered atomic
|
||
|
|
define i32 @non_local_fre(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_fre(
|
||
|
|
; CHECK: load atomic i32, i32* %P1
|
||
|
|
; CHECK: ret i32 0
|
||
|
|
; CHECK: ret i32 0
|
||
|
|
%a = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
ret i32 %a
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
%res = sub i32 %a, %b
|
||
|
|
ret i32 %res
|
||
|
|
}
|
||
|
|
|
||
|
|
; unordered atomic to non-atomic
|
||
|
|
define i32 @non_local_fre2(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_fre2(
|
||
|
|
; CHECK: load atomic i32, i32* %P1
|
||
|
|
; CHECK: ret i32 0
|
||
|
|
; CHECK: ret i32 0
|
||
|
|
%a = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
ret i32 %a
|
||
|
|
next:
|
||
|
|
%b = load i32, i32* %P1
|
||
|
|
%res = sub i32 %a, %b
|
||
|
|
ret i32 %res
|
||
|
|
}
|
||
|
|
|
||
|
|
; Can't forward ordered atomics.
|
||
|
|
define i32 @non_local_fre3(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_fre3(
|
||
|
|
; CHECK: load atomic i32, i32* %P1 acquire
|
||
|
|
; CHECK: ret i32 0
|
||
|
|
; CHECK: load atomic i32, i32* %P1 acquire
|
||
|
|
; CHECK: ret i32 %res
|
||
|
|
%a = load atomic i32, i32* %P1 acquire, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
ret i32 %a
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 acquire, align 4
|
||
|
|
%res = sub i32 %a, %b
|
||
|
|
ret i32 %res
|
||
|
|
}
|
||
|
|
|
||
|
|
declare void @clobber()
|
||
|
|
|
||
|
|
; unordered atomic to unordered atomic
|
||
|
|
define i32 @non_local_pre(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre(
|
||
|
|
; CHECK: load atomic i32, i32* %P1 unordered
|
||
|
|
; CHECK: load atomic i32, i32* %P1 unordered
|
||
|
|
; CHECK: %b = phi i32 [ %b.pre, %early ], [ %a, %0 ]
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|
||
|
|
; unordered atomic to non-atomic
|
||
|
|
define i32 @non_local_pre2(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre2(
|
||
|
|
; CHECK: load atomic i32, i32* %P1 unordered
|
||
|
|
; CHECK: load i32, i32* %P1
|
||
|
|
; CHECK: %b = phi i32 [ %b.pre, %early ], [ %a, %0 ]
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load i32, i32* %P1
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|
||
|
|
; non-atomic to unordered atomic - can't forward!
|
||
|
|
define i32 @non_local_pre3(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre3(
|
||
|
|
; CHECK: %a = load i32, i32* %P1
|
||
|
|
; CHECK: %b = load atomic i32, i32* %P1 unordered
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load i32, i32* %P1
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|
||
|
|
; ordered atomic to ordered atomic - can't forward
|
||
|
|
define i32 @non_local_pre4(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre4(
|
||
|
|
; CHECK: %a = load atomic i32, i32* %P1 seq_cst
|
||
|
|
; CHECK: %b = load atomic i32, i32* %P1 seq_cst
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load atomic i32, i32* %P1 seq_cst, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 seq_cst, align 4
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|
||
|
|
; can't remove volatile on any path
|
||
|
|
define i32 @non_local_pre5(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre5(
|
||
|
|
; CHECK: %a = load atomic i32, i32* %P1 seq_cst
|
||
|
|
; CHECK: %b = load volatile i32, i32* %P1
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load atomic i32, i32* %P1 seq_cst, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load volatile i32, i32* %P1
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
; ordered atomic to unordered atomic
|
||
|
|
define i32 @non_local_pre6(i32* %P1) {
|
||
|
|
; CHECK-LABEL: @non_local_pre6(
|
||
|
|
; CHECK: load atomic i32, i32* %P1 seq_cst
|
||
|
|
; CHECK: load atomic i32, i32* %P1 unordered
|
||
|
|
; CHECK: %b = phi i32 [ %b.pre, %early ], [ %a, %0 ]
|
||
|
|
; CHECK: ret i32 %b
|
||
|
|
%a = load atomic i32, i32* %P1 seq_cst, align 4
|
||
|
|
%cmp = icmp eq i32 %a, 0
|
||
|
|
br i1 %cmp, label %early, label %next
|
||
|
|
early:
|
||
|
|
call void @clobber()
|
||
|
|
br label %next
|
||
|
|
next:
|
||
|
|
%b = load atomic i32, i32* %P1 unordered, align 4
|
||
|
|
ret i32 %b
|
||
|
|
}
|
||
|
|
|