[ARM] Change default ABI for AArch32 to be "aapcs" (was "apcs-gnu")

[olista01]

Summary

The current default abi when no environment is given is "apcs-gnu",
which is obsolete. This patch changes the default to "aapcs". "aapcs" has both
hard- and soft-float variants, so the -mhard-float, -msoft-float and
-mfloat-abi= options now all behave as expected when no environment is
specified in the triple.

While writing this I also noticed that a preprocessor test claims to be
checking darwin, but is actually checking the defaults, which are
different for darwin.

[asl]

LGTM

[olista01]

Thanks, committed revision 216662.

lib/Driver/Tools.cpp

if (Arg *A = Args.getLastArg(options::OPT_mabi_EQ)) {
     switch(Triple.getEnvironment()) {
     case llvm::Triple::Android:
     case llvm::Triple::GNUEABI:
     case llvm::Triple::GNUEABIHF:
       ABIName = "aapcs-linux";
       break;
     case llvm::Triple::EABIHF:
     case llvm::Triple::EABI:
+    default:
       ABIName = "aapcs";
       break;
-    default:
-      ABIName = "apcs-gnu";
     }
   }
   CmdArgs.push_back("-target-abi");
   CmdArgs.push_back(ABIName);
 
   // Determine floating point ABI from the options & target defaults.
   StringRef FloatABI = tools::arm::getARMFloatABI(D, Args, Triple);
   if (FloatABI == "soft") {

test/Driver/arm-abi.c

+// The default ABI is aapcs
+// RUN: %clang -target arm--- %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+// RUN: %clang -target armeb--- %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+// RUN: %clang -target thumb--- %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+// RUN: %clang -target thumbeb--- %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+
+// MachO targets default to apcs-gnu, except for m-class processors
+// RUN: %clang -target arm--darwin- -arch armv7s %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-APCS-GNU %s
+// RUN: %clang -target thumb--darwin- -arch armv7s %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-APCS-GNU %s
+// RUN: %clang -target thumb--darwin- -arch armv7m %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+
+// Windows targets default to AAPCS, regardless of environment
+// RUN: %clang -target arm--windows-gnueabi %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+
+// Otherwise, ABI is celected based on environment
+// RUN: %clang -target arm---android %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS-LINUX %s
+// RUN: %clang -target arm---gnueabi %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS-LINUX %s
+// RUN: %clang -target arm---gnueabihf %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS-LINUX %s
+// RUN: %clang -target arm---eabi %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+// RUN: %clang -target arm---eabihf %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+
+// ABI can be overridden by the -mabi= option
+// RUN: %clang -target arm---eabi -mabi=apcs-gnu %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-APCS-GNU %s
+// RUN: %clang -target arm---gnueabi -mabi=aapcs %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS %s
+// RUN: %clang -target arm---eabi -mabi=aapcs-linux %s -### -o %t.o 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHECK-AAPCS-LINUX %s
+
+// CHECK-APCS-GNU: "-target-abi" "apcs-gnu"
+// CHECK-AAPCS: "-target-abi" "aapcs"
+// CHECK-AAPCS-LINUX: "-target-abi" "aapcs-linux"

test/Preprocessor/init.c

 // ARM-NETBSD:#define __WCHAR_MAX__ 2147483647
 // ARM-NETBSD:#define __WCHAR_TYPE__ int
 // ARM-NETBSD:#define __WCHAR_WIDTH__ 32
 // ARM-NETBSD:#define __WINT_TYPE__ int
 // ARM-NETBSD:#define __WINT_WIDTH__ 32
 // ARM-NETBSD:#define __arm 1
 // ARM-NETBSD:#define __arm__ 1
 
-// RUN: %clang -target arm -arch armv7s -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
-// RUN: %clang -target arm -arch armv6m -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
-// RUN: %clang -target arm -arch armv7m -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
-// RUN: %clang -target arm -arch armv7em -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
+// RUN: %clang -target arm-apple-darwin-eabi -arch armv7s -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
+// RUN: %clang -target arm-apple-darwin-eabi -arch armv6m -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-EABI %s
+// RUN: %clang -target arm-apple-darwin-eabi -arch armv7m -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-EABI %s
+// RUN: %clang -target arm-apple-darwin-eabi -arch armv7em -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-EABI %s
 // RUN: %clang -target thumbv7-apple-darwin-eabi -arch armv7 -x c -E -dM %s -o - | FileCheck --check-prefix=ARM-DARWIN-NO-EABI %s
 // ARM-DARWIN-NO-EABI-NOT: #define __ARM_EABI__ 1
+// ARM-DARWIN-EABI: #define __ARM_EABI__ 1
 
 // Check that -mhwdiv works properly for targets which don't have the hwdiv feature enabled by default.
 
 // RUN: %clang -target arm -mhwdiv=arm -x c -E -dM %s -o - | FileCheck --check-prefix=ARMHWDIV-ARM %s
 // ARMHWDIV-ARM:#define __ARM_ARCH_EXT_IDIV__ 1
 
 // RUN: %clang -target arm -mthumb -mhwdiv=thumb -x c -E -dM %s -o - | FileCheck --check-prefix=THUMBHWDIV-THUMB %s
 // THUMBHWDIV-THUMB:#define __ARM_ARCH_EXT_IDIV__ 1