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authorStephen Hines <srhines@google.com>2014-07-21 00:45:20 -0700
committerStephen Hines <srhines@google.com>2014-07-21 00:45:20 -0700
commitc6a4f5e819217e1e12c458aed8e7b122e23a3a58 (patch)
tree81b7dd2bb4370a392f31d332a566c903b5744764 /test/Transforms/GVN/calloc-load-removal.ll
parent19c6fbb3e8aaf74093afa08013134b61fa08f245 (diff)
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Update LLVM for rebase to r212749.
Includes a cherry-pick of: r212948 - fixes a small issue with atomic calls Change-Id: Ib97bd980b59f18142a69506400911a6009d9df18
Diffstat (limited to 'test/Transforms/GVN/calloc-load-removal.ll')
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diff --git a/test/Transforms/GVN/calloc-load-removal.ll b/test/Transforms/GVN/calloc-load-removal.ll
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+++ b/test/Transforms/GVN/calloc-load-removal.ll
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+; RUN: opt -S -basicaa -gvn < %s | FileCheck %s
+; RUN: opt -S -basicaa -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* %2, align 4
+ ret i32 %3
+
+; CHECK-LABEL: @test1(
+; CHECK-NOT: %3 = load i32* %2, align 4
+; CHECK: ret i32 0
+
+; CHECK_NO_LIBCALLS-LABEL: @test1(
+; CHECK_NO_LIBCALLS: load
+; CHECK_NO_LIBCALLS: ret i32 %
+
+}
+
+declare noalias i8* @calloc(i64, i64)