50 строки
1.5 KiB
LLVM
50 строки
1.5 KiB
LLVM
; RUN: opt -loop-accesses -analyze < %s | FileCheck %s
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; In this loop just because we access A through different types (int, float)
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; we still have a dependence cycle:
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;
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; for (i = 0; i < n; i++) {
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; A_float = (float *) A;
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; A_float[i + 1] = A[i] * B[i];
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; }
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target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
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target triple = "x86_64-apple-macosx10.10.0"
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; CHECK: Report: unsafe dependent memory operations in loop
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; CHECK-NOT: Memory dependences are safe
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@B = common global i32* null, align 8
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@A = common global i32* null, align 8
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define void @f() {
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entry:
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%a = load i32*, i32** @A, align 8
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%b = load i32*, i32** @B, align 8
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br label %for.body
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for.body: ; preds = %for.body, %entry
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%storemerge3 = phi i64 [ 0, %entry ], [ %add, %for.body ]
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%arrayidxA = getelementptr inbounds i32, i32* %a, i64 %storemerge3
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%loadA = load i32, i32* %arrayidxA, align 2
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%arrayidxB = getelementptr inbounds i32, i32* %b, i64 %storemerge3
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%loadB = load i32, i32* %arrayidxB, align 2
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%mul = mul i32 %loadB, %loadA
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%add = add nuw nsw i64 %storemerge3, 1
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%a_float = bitcast i32* %a to float*
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%arrayidxA_plus_2 = getelementptr inbounds float, float* %a_float, i64 %add
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%mul_float = sitofp i32 %mul to float
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store float %mul_float, float* %arrayidxA_plus_2, align 2
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%exitcond = icmp eq i64 %add, 20
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br i1 %exitcond, label %for.end, label %for.body
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for.end: ; preds = %for.body
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ret void
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}
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