[dsymutil] Implement support for universal mach-o object files.

This patch allows llvm-dsymutil to read universal (aka fat) macho object
files and archives. The patch touches nearly everything in the BinaryHolder,
but it is fairly mechinical: the methods that returned MemoryBufferRefs or
ObjectFiles now return a vector of those, and the high-level access function
takes a triple argument to select the architecture.

There is no support yet for handling fat executables and thus no support for
writing fat object files.

llvm-svn: 243096

3 files changed, 17 insertions, 0 deletions

diff --git a/llvm/test/tools/dsymutil/Inputs/fat-test.c b/llvm/test/tools/dsymutil/Inputs/fat-test.c
new file mode 100644
index 00000000000..42c1fce1ec3
--- /dev/null
+++ b/llvm/test/tools/dsymutil/Inputs/fat-test.c
@@ -0,0 +1,17 @@
+/* Compile with:
+   clang -c -g -arch x86_64h -arch x86_64 -arch i386 fat-test.c
+   libtool -static -o libfat-test.a fat-test.o
+
+   To reduce the size of the fat .o:
+   lipo -thin i386 -o fat-test.i386.o fat-test.o 
+   lipo -thin x86_64 -o fat-test.x86_64.o fat-test.o 
+   lipo -thin x86_64h -o fat-test.x86_64h.o fat-test.o 
+   lipo -create -arch x86_64h fat-test.x86_64h.o -arch x86_64 fat-test.x86_64.o -arch i386 fat-test.i386.o -o fat-test.o -segalign i386 8 -segalign x86_64 8 -segalign x86_64h 8
+ */
+#ifdef __x86_64h__
+int x86_64h_var;
+#elif defined(__x86_64__)
+int x86_64_var;
+#else
+int i386_var;
+#endif
diff --git a/llvm/test/tools/dsymutil/Inputs/fat-test.o b/llvm/test/tools/dsymutil/Inputs/fat-test.o
new file mode 100644
index 00000000000..8159cc74977
--- /dev/null
+++ b/llvm/test/tools/dsymutil/Inputs/fat-test.o
diff --git a/llvm/test/tools/dsymutil/Inputs/libfat-test.a b/llvm/test/tools/dsymutil/Inputs/libfat-test.a
new file mode 100644
index 00000000000..6b34b0fd6f9
--- /dev/null
+++ b/llvm/test/tools/dsymutil/Inputs/libfat-test.a