46 lines
1.2 KiB
LLVM
46 lines
1.2 KiB
LLVM
; RUN: opt -S -passes=gvn < %s | FileCheck %s
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; Check that loads from calloc are recognized as being zero.
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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-S128"
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; Function Attrs: nounwind uwtable
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define i32 @test1() {
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%1 = tail call noalias ptr @calloc(i64 1, i64 4)
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; This load is trivially constant zero
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%2 = load i32, ptr %1, align 4
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ret i32 %2
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; CHECK-LABEL: @test1(
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; CHECK-NOT: %2 = load i32, ptr %1, align 4
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; CHECK: ret i32 0
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; CHECK_NO_LIBCALLS-LABEL: @test1(
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; CHECK_NO_LIBCALLS: load
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; CHECK_NO_LIBCALLS: ret i32 %
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}
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define i32 @as_invoke(i1 %c) personality ptr undef {
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bb3:
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%mem = invoke noalias ptr @calloc(i64 1, i64 4)
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to label %bb4 unwind label %bb1
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bb1:
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%lp = landingpad { ptr, i32 } cleanup
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ret i32 0
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bb4:
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; This load is trivially constant zero
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%res = load i32, ptr %mem, align 4
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ret i32 %res
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; CHECK-LABEL: @as_invoke(
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; CHECK-NOT: %3 = load i32, ptr %2, align 4
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; CHECK: ret i32 0
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; CHECK_NO_LIBCALLS-LABEL: @as_invoke(
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; CHECK_NO_LIBCALLS: load
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; CHECK_NO_LIBCALLS: ret i32 %
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}
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declare noalias ptr @calloc(i64, i64) allockind("alloc,zeroed") allocsize(0,1)
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