r367119 - [ARM] Set default alignment to 64bits

[Simi Pallipurath via cfe-commits]

Author: simpal01
Date: Fri Jul 26 08:05:19 2019
New Revision: 367119

URL: http://llvm.org/viewvc/llvm-project?rev=367119&view=rev
Log:
[ARM] Set default alignment to 64bits

The maximum alignment used by ARM arch
is 64bits, not 128.

This could cause overaligned memory
access for 128 bit neon vector that
have unpredictable behaviour.

This fixes: https://bugs.llvm.org/show_bug.cgi?id=42668

Patch by: Diogo Sampaio(diogo.sampaio at arm.com)

Differential Revision: https://reviews.llvm.org/D65000

Change-Id: I5a62b766491f15dd51e4cfe6625929db897f67e3

Added:
    cfe/trunk/test/CodeGen/ARM/
    cfe/trunk/test/CodeGen/ARM/exception-alignment.cpp
Modified:
    cfe/trunk/lib/Basic/Targets/ARM.cpp
    cfe/trunk/test/SemaCXX/warn-overaligned-type-thrown.cpp

Modified: cfe/trunk/lib/Basic/Targets/ARM.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Basic/Targets/ARM.cpp?rev=367119&r1=367118&r2=367119&view=diff
==============================================================================
--- cfe/trunk/lib/Basic/Targets/ARM.cpp (original)
+++ cfe/trunk/lib/Basic/Targets/ARM.cpp Fri Jul 26 08:05:19 2019
@@ -309,8 +309,9 @@ ARMTargetInfo::ARMTargetInfo(const llvm:
   setAtomic();
 
   // Maximum alignment for ARM NEON data types should be 64-bits (AAPCS)
+  // as well the default alignment
   if (IsAAPCS && (Triple.getEnvironment() != llvm::Triple::Android))
-    MaxVectorAlign = 64;
+    DefaultAlignForAttributeAligned = MaxVectorAlign = 64;
 
   // Do force alignment of members that follow zero length bitfields.  If
   // the alignment of the zero-length bitfield is greater than the member

Added: cfe/trunk/test/CodeGen/ARM/exception-alignment.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/ARM/exception-alignment.cpp?rev=367119&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/ARM/exception-alignment.cpp (added)
+++ cfe/trunk/test/CodeGen/ARM/exception-alignment.cpp Fri Jul 26 08:05:19 2019
@@ -0,0 +1,19 @@
+// Bug: https://bugs.llvm.org/show_bug.cgi?id=42668
+// REQUIRES: arm-registered-target
+// RUN: %clang --target=arm-arm-none-eabi -march=armv8-a -S -emit-llvm -Os -o - %s | FileCheck --check-prefixes=CHECK,A8 %s
+// RUN: %clang --target=arm-linux-androideabi -march=armv8-a -S -emit-llvm -Os -o - %s | FileCheck --check-prefixes=CHECK,A16 %s
+// CHECK: [[E:%[A-z0-9]+]] = tail call i8* @__cxa_allocate_exception
+// CHECK-NEXT: [[BC:%[A-z0-9]+]] = bitcast i8* [[E]] to <2 x i64>*
+// A8-NEXT: store <2 x i64> <i64 1, i64 2>, <2 x i64>* [[BC]], align 8
+// A16-NEXT: store <2 x i64> <i64 1, i64 2>, <2 x i64>* [[BC]], align 16
+#include <arm_neon.h>
+
+int main(void) {
+  try {
+    throw vld1q_u64(((const uint64_t[2]){1, 2}));
+  } catch (uint64x2_t exc) {
+    return 0;
+  }
+  return 1;
+}
+

Modified: cfe/trunk/test/SemaCXX/warn-overaligned-type-thrown.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-overaligned-type-thrown.cpp?rev=367119&r1=367118&r2=367119&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-overaligned-type-thrown.cpp (original)
+++ cfe/trunk/test/SemaCXX/warn-overaligned-type-thrown.cpp Fri Jul 26 08:05:19 2019
@@ -2,11 +2,12 @@
 // RUN: %clang_cc1 -triple arm64-apple-ios10 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions -DUNDERALIGNED %s
 // RUN: %clang_cc1 -triple arm64-apple-tvos10 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions -DUNDERALIGNED %s
 // RUN: %clang_cc1 -triple arm64-apple-watchos4 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions -DUNDERALIGNED %s
+// RUN: %clang_cc1 -triple arm-linux-gnueabi -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions  -DUNDERALIGNED %s
 // RUN: %clang_cc1 -triple x86_64-apple-macosx10.14 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple arm64-apple-ios12 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple arm64-apple-tvos12 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple arm64-apple-watchos5 -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
-// RUN: %clang_cc1 -triple arm-linux-gnueabi -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
+// RUN: %clang_cc1 -triple arm-linux-androideabi -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple aarch64-linux-gnueabi -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple mipsel-linux-gnu -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s
 // RUN: %clang_cc1 -triple mips64el-linux-gnu -verify -fsyntax-only -std=c++11 -fcxx-exceptions -fexceptions %s