Merge commit '7dfcb84fc16b3bf6b2379713b53090757f0a45f9'

Conflicts:
	docs/LangRef.rst
	include/llvm/CodeGen/CallingConvLower.h
	include/llvm/IRReader/IRReader.h
	include/llvm/Target/TargetMachine.h
	lib/CodeGen/CallingConvLower.cpp
	lib/IRReader/IRReader.cpp
	lib/IRReader/LLVMBuild.txt
	lib/IRReader/Makefile
	lib/LLVMBuild.txt
	lib/Makefile
	lib/Support/MemoryBuffer.cpp
	lib/Support/Unix/PathV2.inc
	lib/Target/ARM/ARMBaseInstrInfo.cpp
	lib/Target/ARM/ARMISelLowering.cpp
	lib/Target/ARM/ARMInstrInfo.td
	lib/Target/ARM/ARMSubtarget.cpp
	lib/Target/ARM/ARMTargetMachine.cpp
	lib/Target/Mips/CMakeLists.txt
	lib/Target/Mips/MipsDelaySlotFiller.cpp
	lib/Target/Mips/MipsISelLowering.cpp
	lib/Target/Mips/MipsInstrInfo.td
	lib/Target/Mips/MipsSubtarget.cpp
	lib/Target/Mips/MipsSubtarget.h
	lib/Target/X86/X86FastISel.cpp
	lib/Target/X86/X86ISelDAGToDAG.cpp
	lib/Target/X86/X86ISelLowering.cpp
	lib/Target/X86/X86InstrControl.td
	lib/Target/X86/X86InstrFormats.td
	lib/Transforms/IPO/ExtractGV.cpp
	lib/Transforms/InstCombine/InstCombineCompares.cpp
	lib/Transforms/Utils/SimplifyLibCalls.cpp
	test/CodeGen/X86/fast-isel-divrem.ll
	test/MC/ARM/data-in-code.ll
	tools/Makefile
	tools/llvm-extract/llvm-extract.cpp
	tools/llvm-link/CMakeLists.txt
	tools/opt/CMakeLists.txt
	tools/opt/LLVMBuild.txt
	tools/opt/Makefile
	tools/opt/opt.cpp

1 files changed, 24 insertions, 0 deletions

diff --git a/lib/Support/Unix/Program.inc b/lib/Support/Unix/Program.inc
index 834b1cc5dc..c6cc698e9b 100644
--- a/lib/Support/Unix/Program.inc
+++ b/lib/Support/Unix/Program.inc
@@ -32,6 +32,9 @@
 #if HAVE_FCNTL_H
 #include <fcntl.h>
 #endif
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
 #ifdef HAVE_POSIX_SPAWN
 #include <spawn.h>
 #if !defined(__APPLE__)
@@ -431,4 +434,25 @@ error_code Program::ChangeStderrToBinary(){
   return make_error_code(errc::success);
 }
 
+bool llvm::sys::argumentsFitWithinSystemLimits(ArrayRef<const char*> Args) {
+  static long ArgMax = sysconf(_SC_ARG_MAX);
+
+  // System says no practical limit.
+  if (ArgMax == -1)
+    return true;
+
+  // Conservatively account for space required by environment variables.
+  ArgMax /= 2;
+
+  size_t ArgLength = 0;
+  for (ArrayRef<const char*>::iterator I = Args.begin(), E = Args.end();
+       I != E; ++I) {
+    ArgLength += strlen(*I) + 1;
+    if (ArgLength > size_t(ArgMax)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 }