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691 lines
19 KiB
691 lines
19 KiB
; RUN: opt < %s -S -analyze -scalar-evolution | FileCheck %s
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; Positive and negative tests for inferring flags like nsw from
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; reasoning about how a poison value from overflow would trigger
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; undefined behavior.
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define void @foo() {
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ret void
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}
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; Example where an add should get the nsw flag, so that a sext can be
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; distributed over the add.
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define void @test-add-nsw(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-nsw
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nsw>
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%index32 = add nsw i32 %i, %offset
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; CHECK: %index64 =
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; CHECK: --> {(sext i32 %offset to i64),+,1}<nsw>
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%index64 = sext i32 %index32 to i64
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%ptr = getelementptr inbounds float, float* %input, i64 %index64
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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call void @foo()
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Example where an add should get the nuw flag.
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define void @test-add-nuw(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-nuw
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nuw>
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%index32 = add nuw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nuw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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define void @test-add-nuw-from-icmp(float* %input, i32 %offset,
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i32 %numIterations) {
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; CHECK-LABEL: @test-add-nuw-from-icmp
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nuw>
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%index32 = add nuw i32 %i, %offset
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%cmp = icmp sgt i32 %index32, 0
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%cmp.idx = sext i1 %cmp to i32
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%ptr = getelementptr inbounds float, float* %input, i32 %cmp.idx
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%nexti = add nuw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; With no load to trigger UB from poison, we cannot infer nsw.
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define void @test-add-no-load(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-no-load
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nuw i32 %i, 1
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; The current code is only supposed to look at the loop header, so
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; it should not infer nsw in this case, as that would require looking
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; outside the loop header.
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define void @test-add-not-header(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-not-header
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
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br label %loop2
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loop2:
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Same thing as test-add-not-header, but in this case only the load
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; instruction is outside the loop header.
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define void @test-add-not-header2(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-not-header2
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nsw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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br label %loop2
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loop2:
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Similar to test-add-not-header, but in this case the load
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; instruction may not be executed.
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define void @test-add-not-header3(float* %input, i32 %offset, i32 %numIterations,
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i1* %cond_buf) {
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; CHECK-LABEL: @test-add-not-header3
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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%cond = load volatile i1, i1* %cond_buf
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br i1 %cond, label %loop2, label %exit
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loop2:
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Same thing as test-add-not-header2, except we have a few extra
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; blocks.
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define void @test-add-not-header4(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-not-header4
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nsw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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br label %loop3
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loop3:
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br label %loop4
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loop4:
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br label %loop2
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loop2:
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Demonstrate why we need a Visited set in llvm::isKnownNotFullPoison.
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define void @test-add-not-header5(float* %input, i32 %offset) {
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; CHECK-LABEL: @test-add-not-header5
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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br label %loop
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exit:
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ret void
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}
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; The call instruction makes it not guaranteed that the add will be
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; executed, since it could run forever or throw an exception, so we
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; cannot assume that the UB is realized.
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define void @test-add-call(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-call
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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call void @foo()
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Same issue as test-add-call, but this time the call is between the
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; producer of poison and the load that consumes it.
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define void @test-add-call2(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-call2
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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call void @foo()
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Without inbounds, GEP does not propagate poison in the very
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; conservative approach used here.
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define void @test-add-no-inbounds(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-no-inbounds
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Multiplication by a non-zero constant propagates poison if there is
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; a nuw or nsw flag on the multiplication.
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define void @test-add-mul-propagates(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-mul-propagates
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nsw>
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%index32 = add nsw i32 %i, %offset
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%indexmul = mul nuw i32 %index32, 2
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%ptr = getelementptr inbounds float, float* %input, i32 %indexmul
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Multiplication by a non-constant should not propagate poison in the
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; very conservative approach used here.
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define void @test-add-mul-no-propagation(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-mul-no-propagation
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%indexmul = mul nsw i32 %index32, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %indexmul
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Multiplication by a non-zero constant does not propagate poison
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; without a no-wrap flag.
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define void @test-add-mul-no-propagation2(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-mul-no-propagation2
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nw>
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%index32 = add nsw i32 %i, %offset
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%indexmul = mul i32 %index32, 2
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%ptr = getelementptr inbounds float, float* %input, i32 %indexmul
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Division by poison triggers UB.
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define void @test-add-div(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-div
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %j =
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; CHECK: --> {%offset,+,1}<nsw>
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%j = add nsw i32 %i, %offset
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%q = sdiv i32 %numIterations, %j
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%nexti = add nsw i32 %i, 1
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Remainder of poison by non-poison divisor does not trigger UB.
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define void @test-add-div2(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-div2
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %j =
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; CHECK: --> {%offset,+,1}<nw>
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%j = add nsw i32 %i, %offset
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%q = sdiv i32 %j, %numIterations
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%nexti = add nsw i32 %i, 1
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Store to poison address triggers UB.
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define void @test-add-store(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-store
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {%offset,+,1}<nsw>
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%index32 = add nsw i32 %i, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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store float 1.0, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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exit:
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ret void
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}
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; Three sequential adds where the middle add should have nsw. There is
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; a special case for sequential adds and this test covers that. We have to
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; put the final add first in the program since otherwise the special case
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; is not triggered, hence the strange basic block ordering.
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define void @test-add-twice(float* %input, i32 %offset, i32 %numIterations) {
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; CHECK-LABEL: @test-add-twice
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entry:
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br label %loop
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loop2:
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; CHECK: %seq =
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; CHECK: --> {(2 + %offset),+,1}<nw>
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%seq = add nsw nuw i32 %index32, 1
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%exitcond = icmp eq i32 %nexti, %numIterations
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br i1 %exitcond, label %exit, label %loop
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loop:
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%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
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%j = add nsw i32 %i, 1
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; CHECK: %index32 =
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; CHECK: --> {(1 + %offset)<nsw>,+,1}<nsw>
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%index32 = add nsw i32 %j, %offset
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%ptr = getelementptr inbounds float, float* %input, i32 %index32
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%nexti = add nsw i32 %i, 1
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store float 1.0, float* %ptr, align 4
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br label %loop2
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exit:
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ret void
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}
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; Example where a mul should get the nsw flag, so that a sext can be
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; distributed over the mul.
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define void @test-mul-nsw(float* %input, i32 %stride, i32 %numIterations) {
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; CHECK-LABEL: @test-mul-nsw
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entry:
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br label %loop
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loop:
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%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
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; CHECK: %index32 =
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; CHECK: --> {0,+,%stride}<nsw>
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%index32 = mul nsw i32 %i, %stride
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; CHECK: %index64 =
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; CHECK: --> {0,+,(sext i32 %stride to i64)}<nsw>
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%index64 = sext i32 %index32 to i64
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%ptr = getelementptr inbounds float, float* %input, i64 %index64
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%nexti = add nsw i32 %i, 1
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%f = load float, float* %ptr, align 4
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%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a mul should get the nuw flag.
|
|
define void @test-mul-nuw(float* %input, i32 %stride, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-mul-nuw
|
|
entry:
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {0,+,%stride}<nuw>
|
|
%index32 = mul nuw i32 %i, %stride
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i32 %index32
|
|
%nexti = add nuw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a shl should get the nsw flag, so that a sext can be
|
|
; distributed over the shl.
|
|
define void @test-shl-nsw(float* %input, i32 %start, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-shl-nsw
|
|
entry:
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ %start, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {(256 * %start),+,256}<nsw>
|
|
%index32 = shl nsw i32 %i, 8
|
|
|
|
; CHECK: %index64 =
|
|
; CHECK: --> {(sext i32 (256 * %start) to i64),+,256}<nsw>
|
|
%index64 = sext i32 %index32 to i64
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i64 %index64
|
|
%nexti = add nsw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a shl should get the nuw flag.
|
|
define void @test-shl-nuw(float* %input, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-shl-nuw
|
|
entry:
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {0,+,512}<nuw>
|
|
%index32 = shl nuw i32 %i, 9
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i32 %index32
|
|
%nexti = add nuw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a sub should *not* get the nsw flag, because of how
|
|
; scalar evolution represents A - B as A + (-B) and -B can wrap even
|
|
; in cases where A - B does not.
|
|
define void @test-sub-no-nsw(float* %input, i32 %start, i32 %sub, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-sub-no-nsw
|
|
entry:
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ %start, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {((-1 * %sub) + %start),+,1}<nw>
|
|
%index32 = sub nsw i32 %i, %sub
|
|
%index64 = sext i32 %index32 to i64
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i64 %index64
|
|
%nexti = add nsw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a sub should get the nsw flag as the RHS cannot be the
|
|
; minimal signed value.
|
|
define void @test-sub-nsw(float* %input, i32 %start, i32 %sub, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-sub-nsw
|
|
entry:
|
|
%halfsub = ashr i32 %sub, 1
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ %start, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {((-1 * %halfsub)<nsw> + %start)<nsw>,+,1}<nsw>
|
|
%index32 = sub nsw i32 %i, %halfsub
|
|
%index64 = sext i32 %index32 to i64
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i64 %index64
|
|
%nexti = add nsw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Example where a sub should get the nsw flag, since the LHS is non-negative,
|
|
; which implies that the RHS cannot be the minimal signed value.
|
|
define void @test-sub-nsw-lhs-non-negative(float* %input, i32 %sub, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-sub-nsw-lhs-non-negative
|
|
entry:
|
|
br label %loop
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop ], [ 0, %entry ]
|
|
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {(-1 * %sub),+,1}<nsw>
|
|
%index32 = sub nsw i32 %i, %sub
|
|
|
|
; CHECK: %index64 =
|
|
; CHECK: --> {(sext i32 (-1 * %sub) to i64),+,1}<nsw>
|
|
%index64 = sext i32 %index32 to i64
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i64 %index64
|
|
%nexti = add nsw i32 %i, 1
|
|
%f = load float, float* %ptr, align 4
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
; Two adds with a sub in the middle and the sub should have nsw. There is
|
|
; a special case for sequential adds/subs and this test covers that. We have to
|
|
; put the final add first in the program since otherwise the special case
|
|
; is not triggered, hence the strange basic block ordering.
|
|
define void @test-sub-with-add(float* %input, i32 %offset, i32 %numIterations) {
|
|
; CHECK-LABEL: @test-sub-with-add
|
|
entry:
|
|
br label %loop
|
|
loop2:
|
|
; CHECK: %seq =
|
|
; CHECK: --> {(2 + (-1 * %offset)),+,1}<nw>
|
|
%seq = add nsw nuw i32 %index32, 1
|
|
%exitcond = icmp eq i32 %nexti, %numIterations
|
|
br i1 %exitcond, label %exit, label %loop
|
|
|
|
loop:
|
|
%i = phi i32 [ %nexti, %loop2 ], [ 0, %entry ]
|
|
|
|
%j = add nsw i32 %i, 1
|
|
; CHECK: %index32 =
|
|
; CHECK: --> {(1 + (-1 * %offset))<nsw>,+,1}<nsw>
|
|
%index32 = sub nsw i32 %j, %offset
|
|
|
|
%ptr = getelementptr inbounds float, float* %input, i32 %index32
|
|
%nexti = add nsw i32 %i, 1
|
|
store float 1.0, float* %ptr, align 4
|
|
br label %loop2
|
|
exit:
|
|
ret void
|
|
}
|
|
|
|
|
|
; Subtraction of two recurrences. The addition in the SCEV that this
|
|
; maps to is NSW, but the negation of the RHS does not since that
|
|
; recurrence could be the most negative representable value.
|
|
define void @subrecurrences(i32 %outer_l, i32 %inner_l, i32 %val) {
|
|
; CHECK-LABEL: @subrecurrences
|
|
entry:
|
|
br label %outer
|
|
|
|
outer:
|
|
%o_idx = phi i32 [ 0, %entry ], [ %o_idx.inc, %outer.be ]
|
|
%o_idx.inc = add nsw i32 %o_idx, 1
|
|
%cond = icmp eq i32 %o_idx, %val
|
|
br i1 %cond, label %inner, label %outer.be
|
|
|
|
inner:
|
|
%i_idx = phi i32 [ 0, %outer ], [ %i_idx.inc, %inner ]
|
|
%i_idx.inc = add nsw i32 %i_idx, 1
|
|
; CHECK: %v =
|
|
; CHECK-NEXT: --> {{[{][{]}}-1,+,-1}<nw><%outer>,+,1}<nsw><%inner>
|
|
%v = sub nsw i32 %i_idx, %o_idx.inc
|
|
%forub = udiv i32 1, %v
|
|
%cond2 = icmp eq i32 %i_idx, %inner_l
|
|
br i1 %cond2, label %outer.be, label %inner
|
|
|
|
outer.be:
|
|
%cond3 = icmp eq i32 %o_idx, %outer_l
|
|
br i1 %cond3, label %exit, label %outer
|
|
|
|
exit:
|
|
ret void
|
|
}
|