[mips][clang] Do not define __GCC_HAVE_SYNC_COMPARE_AND_SWAP macros for MIPS-I

[brad]

Summary

Do not define __GCC_HAVE_SYNC_COMPARE_AND_SWAP macros for MIPS-I

[MaskRay]

Looks great!

clang/lib/Basic/Targets/Mips.cpp

void MipsTargetInfo::getTargetDefines(const LangOptions &Opts,
   if (CPU == "octeon+")
     Builder.defineMacro("_MIPS_ARCH_OCTEONP");
   else
     Builder.defineMacro("_MIPS_ARCH_" + StringRef(CPU).upper());
 
   if (StringRef(CPU).startswith("octeon"))
     Builder.defineMacro("__OCTEON__");
 
-  // These shouldn't be defined for MIPS-I but there's no need to check
-  // for that since MIPS-I isn't supported.
+  if (CPU != "mips1") {
     Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_1");
     Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_2");
     Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4");
+  }
 
   // 32-bit MIPS processors don't have the necessary lld/scd instructions
   // found in 64-bit processors. In the case of O32 on a 64-bit processor,
   // the instructions exist but using them violates the ABI since they
   // require 64-bit GPRs and O32 only supports 32-bit GPRs.
   if (ABI == "n32" || ABI == "n64")
     Builder.defineMacro("__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8");
 }

clang/test/Preprocessor/predefined-macros.c

 // CHECK-SYNC_CAS_ARMv7: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
 // CHECK-SYNC_CAS_ARMv7: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
 // CHECK-SYNC_CAS_ARMv7: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
 //
 // RUN: %clang_cc1 %s -E -dM -o - -triple armv6 -target-cpu cortex-m0 \
 // RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-SYNC_CAS_ARMv6
 // CHECK-SYNC_CAS_ARMv6-NOT: __GCC_HAVE_SYNC_COMPARE_AND_SWAP
 //
+// RUN: %clang_cc1 %s -E -dM -o - -triple mips -target-cpu mips1 \
+// RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-SYNC_CAS_MIPS32_MIPS1
 // RUN: %clang_cc1 %s -E -dM -o - -triple mips -target-cpu mips2 \
 // RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-SYNC_CAS_MIPS \
 // RUN:         --check-prefix=CHECK-SYNC_CAS_MIPS32
 // RUN: %clang_cc1 %s -E -dM -o - -triple mips64 -target-cpu mips3 \
 // RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-SYNC_CAS_MIPS \
 // RUN:         --check-prefix=CHECK-SYNC_CAS_MIPS64
+// CHECK-SYNC_CAS_MIPS32_MIPS1-NOT: __GCC_HAVE_SYNC_COMPARE_AND_SWAP
 // CHECK-SYNC_CAS_MIPS: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_1 1
 // CHECK-SYNC_CAS_MIPS: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_2 1
 // CHECK-SYNC_CAS_MIPS: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 1
 // CHECK-SYNC_CAS_MIPS32-NOT: __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8
 // CHECK-SYNC_CAS_MIPS64: #define __GCC_HAVE_SYNC_COMPARE_AND_SWAP_8 1
 
 // RUN: %clang_cc1 %s -E -dM -o - -x cl \
 // RUN:   | FileCheck -match-full-lines %s --check-prefix=CHECK-CL12