Allow case-insensitive values for -mcpu 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 -mcpu option for the AArch64 target.

[richard.barton.arm]

I have one comment about a missing regression test, but otherwise this patch seems fine to me. I understand the previous version broke the ARM bot, so I will let Renato have last say.

test/Driver/aarch64-cpus.c

114

It seems your patch also allows mixed case in the +feature part of the argument. This is in line with GCC 4.9, but I would expect a regression test checking that here.

[enefaim]

New in this version:

• Added tests for the +feature part of -mcpu.

[rengolin]

The ARM side should be fixed already. LGTM. Thanks!

Let's see what the bots think about it... :)

[enefaim]

r239619

lib/Driver/Tools.cpp

 static std::string getAArch64TargetCPU(const ArgList &Args) {
   Arg *A;
   std::string CPU;
   // If we have -mtune or -mcpu, use that.
   if ((A = Args.getLastArg(options::OPT_mtune_EQ))) {
     CPU = A->getValue();
   } else if ((A = Args.getLastArg(options::OPT_mcpu_EQ))) {
     StringRef Mcpu = A->getValue();
-    CPU = Mcpu.split("+").first;
+    CPU = Mcpu.split("+").first.lower();
   }
 
   // Handle CPU name is 'native'.
   if (CPU == "native")
     return llvm::sys::getHostCPUName();
   else if (CPU.size())
     return CPU;
 

   return true;
 }
 
 static bool
 getAArch64ArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu,
                                const ArgList &Args,
                                std::vector<const char *> &Features) {
   StringRef CPU;
-  if (!DecodeAArch64Mcpu(D, Mcpu, CPU, Features))
+  std::string McpuLowerCase = Mcpu.lower();
+  if (!DecodeAArch64Mcpu(D, McpuLowerCase, CPU, Features))
     return false;
 
   return true;
 }
 
 static bool
 getAArch64MicroArchFeaturesFromMtune(const Driver &D, StringRef Mtune,
                                      const ArgList &Args,

 }
 
 static bool
 getAArch64MicroArchFeaturesFromMcpu(const Driver &D, StringRef Mcpu,
                                     const ArgList &Args,
                                     std::vector<const char *> &Features) {
   StringRef CPU;
   std::vector<const char *> DecodedFeature;
-  if (!DecodeAArch64Mcpu(D, Mcpu, CPU, DecodedFeature))
+  std::string McpuLowerCase = Mcpu.lower();
+  if (!DecodeAArch64Mcpu(D, McpuLowerCase, CPU, DecodedFeature))
     return false;
 
   return getAArch64MicroArchFeaturesFromMtune(D, CPU, Args, Features);
 }
 
 static void getAArch64TargetFeatures(const Driver &D, const ArgList &Args,
                                      std::vector<const char *> &Features) {
   Arg *A;

test/Driver/aarch64-cpus.c

 // 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"