Allow case-insensitive values for -march for AArch64 target in line with GCC.

[enefaim]

Summary

GCC allows case-insensitive values for -mcpu, -march and -mtune options.
This patch implements the same behaviour for the -march option for the AArch64 target.

[richard.barton.arm]

Again no test that the case insensitivity also applies to the feature extensions. Other than that, this seems the same as the previous patch about -mcpu and I see no reason not to commit it.

[rengolin]

LGTM, thanks!

[enefaim]

Hi Richard,

In D10535#190213, @richard.barton.arm wrote:

Again no test that the case insensitivity also applies to the feature extensions. Other than that, this seems the same as the previous patch about -mcpu and I see no reason not to commit it.

I added the feature tests for the final version of the patch.

Thanks,
Gabor

[enefaim]

r240019

lib/Driver/Tools.cpp

 
   return true;
 }
 
 static bool
 getAArch64ArchFeaturesFromMarch(const Driver &D, StringRef March,
                                 const ArgList &Args,
                                 std::vector<const char *> &Features) {
-  std::pair<StringRef, StringRef> Split = March.split("+");
+  std::string MarchLowerCase = March.lower();
+  std::pair<StringRef, StringRef> Split = StringRef(MarchLowerCase).split("+");
 
   if (Split.first == "armv8-a" ||
       Split.first == "armv8a") {
     // ok, no additional features.
   } else if (
       Split.first == "armv8.1-a" ||
       Split.first == "armv8.1a" ) {
     Features.push_back("+v8.1a");

test/Driver/aarch64-cpus.c

 // ARM64-GENERICV81A: "-cc1"{{.*}} "-triple" "arm64{{.*}}" "-target-cpu" "generic" "-target-feature" "+neon" "-target-feature" "+v8.1a"
 
 // RUN: %clang -target aarch64_be -march=armv8.1a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // RUN: %clang -target aarch64_be -march=armv8.1-a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // RUN: %clang -target aarch64 -mbig-endian -march=armv8.1a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // RUN: %clang -target aarch64 -mbig-endian -march=armv8.1-a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // RUN: %clang -target aarch64_be -mbig-endian -march=armv8.1a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // RUN: %clang -target aarch64_be -mbig-endian -march=armv8.1-a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// ================== Check whether -march accepts mixed-case values.
+// RUN: %clang -target aarch64_be -march=ARMV8.1A -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// RUN: %clang -target aarch64_be -march=ARMV8.1-A -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// RUN: %clang -target aarch64 -mbig-endian -march=Armv8.1A -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// RUN: %clang -target aarch64 -mbig-endian -march=Armv8.1-A -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// RUN: %clang -target aarch64_be -mbig-endian -march=ARMv8.1a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
+// RUN: %clang -target aarch64_be -mbig-endian -march=ARMV8.1-a -### -c %s 2>&1 | FileCheck -check-prefix=GENERICV81A-BE %s
 // GENERICV81A-BE: "-cc1"{{.*}} "-triple" "aarch64_be{{.*}}" "-target-cpu" "generic" "-target-feature" "+neon" "-target-feature" "+v8.1a"
 
 // ================== Check whether -mcpu accepts mixed-case values.
 // RUN: %clang -target aarch64 -mcpu=Cortex-a53 -### -c %s 2>&1 | FileCheck -check-prefix=CASE-INSENSITIVE-CA53 %s
 // CASE-INSENSITIVE-CA53: "-cc1"{{.*}} "-triple" "aarch64{{.*}}" "-target-cpu" "cortex-a53"
 
 // RUN: %clang -target arm64 -mcpu=cortex-A53 -### -c %s 2>&1 | FileCheck -check-prefix=CASE-INSENSITIVE-ARM64-CA53 %s
 // CASE-INSENSITIVE-ARM64-CA53: "-cc1"{{.*}} "-triple" "arm64{{.*}}" "-target-cpu" "cortex-a53"
 
 // RUN: %clang -target aarch64 -mcpu=CORTEX-A57 -### -c %s 2>&1 | FileCheck -check-prefix=CASE-INSENSITIVE-CA57 %s
 // CASE-INSENSITIVE-CA57: "-cc1"{{.*}} "-triple" "aarch64{{.*}}" "-target-cpu" "cortex-a57"
 
 // RUN: %clang -target arm64 -mcpu=Cortex-A57 -### -c %s 2>&1 | FileCheck -check-prefix=CASE-INSENSITIVE-ARM64-CA57 %s
 // CASE-INSENSITIVE-ARM64-CA57: "-cc1"{{.*}} "-triple" "arm64{{.*}}" "-target-cpu" "cortex-a57"