Fixing compiler_rt makefile for architecture i686.

[nishanth-kottary]

Summary

Added a check for architecture i686 to treat it as i386.

[loladiro]

Note that this is bug https://llvm.org/bugs/show_bug.cgi?id=23063.

[samsonov]

Suppose you build the compiler-rt runtimes like that, and they will have i386 in their name. Will Clang on your host be able to properly pick them up, instead of looking for i686 libs?

[nishanth-kottary]

Added code handle i686 architecture in makefiles. Built files will now have i686 in their names.

[samsonov]

Before we proceed with this review - please elaborate why you need the support for this in autoconf build system. It's kind of being actively deprecated right now (at least on Linux) - for instance Clang 3.7 release would be built using CMake.

[loladiro]

CMake doesn't quite produce the same output as the autotools build yet, so in the meantime we'd like to avoid the build just failing. Plus fixing this upstream makes it easier to just backport it to versions in which we can't use CMake.

lib/builtins/i386/Makefile.mk

 
 ModuleName := builtins
 SubDirs := 
-OnlyArchs := i386
+OnlyArchs := i386 i686
 
 AsmSources := $(foreach file,$(wildcard $(Dir)/*.S),$(notdir $(file)))
 Sources := $(foreach file,$(wildcard $(Dir)/*.c),$(notdir $(file)))

make/platform/clang_linux.mk

 
 # Define configs only if arch in triple is i386 or x86_64
 CompilerTargetArch := $(firstword $(subst -, ,$(CompilerTargetTriple)))
-ifeq ($(call contains,i386 x86_64,$(CompilerTargetArch)),true)
+ifeq ($(call contains,i386 i686 x86_64,$(CompilerTargetArch)),true)
 
 # TryCompile compiler source flags
 # Returns exit code of running a compiler invocation.

     echo $$?)
 
 test_source = $(ProjSrcRoot)/make/platform/clang_linux_test_input.c
-ifeq ($(CompilerTargetArch),i386)
-  SupportedArches := i386
+ifeq ($(call contains,i386 i686,$(CompilerTargetArch)),true)
+  SupportedArches := $(CompilerTargetArch)
   ifeq ($(call TryCompile,$(CC),$(test_source),-m64),0)
     SupportedArches += x86_64
   endif

 Arch.profile-i386 := i386
 endif
 
+# Build runtime libraries for i686.
+ifeq ($(call contains,$(SupportedArches),i686),true)
+Configs += builtins-i686 profile-i686
+Arch.builtins-i686 := i686
+Arch.profile-i686 := i686
+endif
+
 # Build runtime libraries for x86_64.
 ifeq ($(call contains,$(SupportedArches),x86_64),true)
 Configs += builtins-x86_64 profile-x86_64

 CFLAGS := -Wall -Werror -O3 -fomit-frame-pointer
 
 CFLAGS.builtins-i386 := $(CFLAGS) -m32
+CFLAGS.builtins-i686 := $(CFLAGS) -m32
 CFLAGS.builtins-x86_64 := $(CFLAGS) -m64
 CFLAGS.profile-i386 := $(CFLAGS) -m32
+CFLAGS.profile-i686 := $(CFLAGS) -m32
 CFLAGS.profile-x86_64 := $(CFLAGS) -m64
 
 FUNCTIONS.builtins-i386 := $(CommonFunctions) $(ArchFunctions.i386)
+FUNCTIONS.builtins-i686 := $(CommonFunctions) $(ArchFunctions.i686)
 FUNCTIONS.builtins-x86_64 := $(CommonFunctions) $(ArchFunctions.x86_64)
 FUNCTIONS.profile-i386 := GCDAProfiling InstrProfiling InstrProfilingBuffer \
                           InstrProfilingFile InstrProfilingPlatformOther \
                           InstrProfilingRuntime InstrProfilingUtil
+FUNCTIONS.profile-i686 := GCDAProfiling InstrProfiling InstrProfilingBuffer \
+                          InstrProfilingFile InstrProfilingPlatformOther \
+                          InstrProfilingRuntime InstrProfilingUtil
 FUNCTIONS.profile-x86_64 := $(FUNCTIONS.profile-i386)
 
 # Always use optimized variants.