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; RUN: opt -S -basic-aa -gvn < %s | FileCheck %s
; RUN: opt -S -basic-aa -gvn -disable-simplify-libcalls < %s | FileCheck %s -check-prefix=CHECK_NO_LIBCALLS
; Check that loads from calloc are recognized as being zero.
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"
; Function Attrs: nounwind uwtable
define i32 @test1() {
%1 = tail call noalias i8* @calloc(i64 1, i64 4)
%2 = bitcast i8* %1 to i32*
; This load is trivially constant zero
%3 = load i32, i32* %2, align 4
ret i32 %3
; CHECK-LABEL: @test1(
; CHECK-NOT: %3 = load i32, i32* %2, align 4
; CHECK: ret i32 0
; CHECK_NO_LIBCALLS-LABEL: @test1(
; CHECK_NO_LIBCALLS: load
; CHECK_NO_LIBCALLS: ret i32 %
}
define i32 @as_invoke(i1 %c) personality i32 (...)* undef {
bb3:
%mem = invoke noalias i8* @calloc(i64 1, i64 4)
to label %bb4 unwind label %bb1
bb1:
%lp = landingpad { i8*, i32 } cleanup
ret i32 0
bb4:
%mem.i32 = bitcast i8* %mem to i32*
; This load is trivially constant zero
%res = load i32, i32* %mem.i32, align 4
ret i32 %res
; CHECK-LABEL: @as_invoke(
; CHECK-NOT: %3 = load i32, i32* %2, align 4
; CHECK: ret i32 0
; CHECK_NO_LIBCALLS-LABEL: @as_invoke(
; CHECK_NO_LIBCALLS: load
; CHECK_NO_LIBCALLS: ret i32 %
}
declare noalias i8* @calloc(i64, i64)
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