[mips] Support building compiler-rt with gcc.

Summary:
This will allow us to enable it on the buildbot (and then enable a
sanitizer buildbot).

The problem is that gcc for Mips does not accept -m32/-m64 like clang does.
We therefore need to use the nearest equivalent -mips32r2/-mips64r2. We must
also specify -mabi=64 in the -mips64r2 case since gcc's default ABI has
traditionally been N32 whereas clang's is N64.

Reviewers: sagar

Reviewed By: sagar

Subscribers: llvm-commits, samsonov, kcc, mohit.bhakkad, Anand.Takale, sagar

Differential Revision: http://reviews.llvm.org/D8892

llvm-svn: 235299

1 files changed, 9 insertions, 4 deletions

diff --git a/compiler-rt/cmake/config-ix.cmake b/compiler-rt/cmake/config-ix.cmake
index 1b7cceb7a79..5574dc2a3e9 100644
--- a/compiler-rt/cmake/config-ix.cmake
+++ b/compiler-rt/cmake/config-ix.cmake
@@ -177,13 +177,18 @@ else()
       test_target_arch(powerpc64le "" "-m64")
     endif()
   elseif("${LLVM_NATIVE_ARCH}" STREQUAL "Mips")
+    # Gcc doesn't accept -m32/-m64 so we do the next best thing and use
+    # -mips32r2/-mips64r2. We don't use -mips1/-mips3 because we want to match
+    # clang's default CPU's. In the 64-bit case, we must also specify the ABI
+    # since the default ABI differs between gcc and clang.
+    # FIXME: Ideally, we would build the N32 library too.
     if("${COMPILER_RT_TEST_TARGET_ARCH}" MATCHES "mipsel|mips64el")
       # regex for mipsel, mips64el
-      test_target_arch(mipsel "" "-m32")
-      test_target_arch(mips64el "" "-m64")
+      test_target_arch(mipsel "" "-mips32r2")
+      test_target_arch(mips64el "" "-mips64r2 -mabi=n64")
     else()
-      test_target_arch(mips "" "-m32")
-      test_target_arch(mips64 "" "-m64")
+      test_target_arch(mips "" "-mips32r2")
+      test_target_arch(mips64 "" "-mips64r2 -mabi=n64")
     endif()
   elseif("${COMPILER_RT_TEST_TARGET_ARCH}" MATCHES "arm")
     test_target_arch(arm "" "-march=armv7-a")