[AArch64] Pass subtarget feature "+strict-align".

This commit changes the driver to save subtarget feature "+strict-align"
to the IR instead of using backend option "aarch64-strict-align". This is
needed for LTO.

rdar://problem/21529937

llvm-svn: 243518

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index f554cae..bd8f25f 100644 (file)
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -983,15 +983,6 @@ void Clang::AddAArch64TargetArgs(const ArgList &Args,
   CmdArgs.push_back("-target-abi");
   CmdArgs.push_back(ABIName);
 
-  if (Arg *A = Args.getLastArg(options::OPT_mno_unaligned_access,
-                               options::OPT_munaligned_access)) {
-    CmdArgs.push_back("-backend-option");
-    if (A->getOption().matches(options::OPT_mno_unaligned_access))
-      CmdArgs.push_back("-aarch64-strict-align");
-    else
-      CmdArgs.push_back("-aarch64-no-strict-align");
-  }
-
   if (Arg *A = Args.getLastArg(options::OPT_mfix_cortex_a53_835769,
                                options::OPT_mno_fix_cortex_a53_835769)) {
     CmdArgs.push_back("-backend-option");
@@ -2068,6 +2059,11 @@ static void getAArch64TargetFeatures(const Driver &D,
       Features.push_back("-crc");
   }
 
+  if (Arg *A = Args.getLastArg(options::OPT_mno_unaligned_access,
+                               options::OPT_munaligned_access))
+    if (A->getOption().matches(options::OPT_mno_unaligned_access))
+      Features.push_back("+strict-align");
+
   if (Args.hasArg(options::OPT_ffixed_x18) || Triple.isOSDarwin())
     Features.push_back("+reserve-x18");
 }

diff --git a/clang/test/Driver/arm-alignment.c b/clang/test/Driver/arm-alignment.c
index 21caf83..21a2919 100644 (file)
--- a/clang/test/Driver/arm-alignment.c
+++ b/clang/test/Driver/arm-alignment.c
@@ -29,7 +29,7 @@
 // RUN: FileCheck --check-prefix=CHECK-UNALIGNED-AARCH64 < %t %s
 
 // CHECK-UNALIGNED-ARM-NOT: "-target-feature" "+strict-align"
-// CHECK-UNALIGNED-AARCH64: "-backend-option" "-aarch64-no-strict-align"
+// CHECK-UNALIGNED-AARCH64-NOT: "-target-feature" "+strict-align"
 
 
 // RUN: %clang -target arm-none-gnueabi -mno-unaligned-access -### %s 2> %t
@@ -75,7 +75,7 @@
 // RUN: FileCheck --check-prefix=CHECK-ALIGNED-AARCH64 < %t %s
 
 // CHECK-ALIGNED-ARM: "-target-feature" "+strict-align"
-// CHECK-ALIGNED-AARCH64: "-backend-option" "-aarch64-strict-align"
+// CHECK-ALIGNED-AARCH64: "-target-feature" "+strict-align"
 
 // Make sure that v6M cores always trigger the unsupported aligned accesses error
 // for all supported architecture triples.