aboutsummaryrefslogtreecommitdiff
path: root/lib/Support/Process.cpp
diff options
context:
space:
mode:
authorDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
committerDerek Schuff <dschuff@chromium.org>2013-01-30 11:34:40 -0800
commit1843e19bce9b11fc840858e136c6c52cf8b42e0b (patch)
treee8bfc928152e2d3b3dd120d141d13dc08a9b49e4 /lib/Support/Process.cpp
parentaa0fa8a8df25807f784ec9ca9deeb40328636595 (diff)
parenta662a9862501fc86904e90054f7c1519101d9126 (diff)
Merge commit 'a662a9862501fc86904e90054f7c1519101d9126'
Conflicts: include/llvm/CodeGen/IntrinsicLowering.h include/llvm/MC/MCAssembler.h include/llvm/MC/MCObjectStreamer.h lib/LLVMBuild.txt lib/Linker/LinkArchives.cpp lib/MC/MCAssembler.cpp lib/MC/MCELFStreamer.cpp lib/MC/MCParser/AsmParser.cpp lib/MC/MCPureStreamer.cpp lib/MC/WinCOFFStreamer.cpp lib/Makefile lib/Support/Unix/Memory.inc lib/Support/Unix/Process.inc lib/Support/Unix/Program.inc lib/Target/ARM/ARM.h lib/Target/ARM/ARMFastISel.cpp lib/Target/ARM/ARMISelLowering.cpp lib/Target/ARM/MCTargetDesc/ARMELFStreamer.cpp lib/Target/Mips/MipsInstrFPU.td lib/Target/X86/CMakeLists.txt lib/Target/X86/X86ISelLowering.cpp lib/Target/X86/X86TargetMachine.cpp lib/Target/X86/X86TargetObjectFile.cpp lib/Transforms/InstCombine/InstCombineCalls.cpp test/CodeGen/X86/fast-isel-x86-64.ll tools/llc/llc.cpp tools/lto/LTOModule.cpp utils/TableGen/EDEmitter.cpp
Diffstat (limited to 'lib/Support/Process.cpp')
-rw-r--r--lib/Support/Process.cpp60
1 files changed, 58 insertions, 2 deletions
diff --git a/lib/Support/Process.cpp b/lib/Support/Process.cpp
index 88ca7c3f22..2c0d37bb32 100644
--- a/lib/Support/Process.cpp
+++ b/lib/Support/Process.cpp
@@ -11,10 +11,11 @@
//
//===----------------------------------------------------------------------===//
-#include "llvm/Support/Process.h"
#include "llvm/Config/config.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Process.h"
-namespace llvm {
+using namespace llvm;
using namespace sys;
//===----------------------------------------------------------------------===//
@@ -22,8 +23,63 @@ using namespace sys;
//=== independent code.
//===----------------------------------------------------------------------===//
+// Empty virtual destructor to anchor the vtable for the process class.
+process::~process() {}
+
+self_process *process::get_self() {
+ // Use a function local static for thread safe initialization and allocate it
+ // as a raw pointer to ensure it is never destroyed.
+ static self_process *SP = new self_process();
+
+ return SP;
}
+#if defined(_MSC_VER)
+// Visual Studio complains that the self_process destructor never exits. This
+// doesn't make much sense, as that's the whole point of calling abort... Just
+// silence this warning.
+#pragma warning(push)
+#pragma warning(disable:4722)
+#endif
+
+// The destructor for the self_process subclass must never actually be
+// executed. There should be at most one instance of this class, and that
+// instance should live until the process terminates to avoid the potential for
+// racy accesses during shutdown.
+self_process::~self_process() {
+ llvm_unreachable("This destructor must never be executed!");
+}
+
+/// \brief A helper function to compute the elapsed wall-time since the program
+/// started.
+///
+/// Note that this routine actually computes the elapsed wall time since the
+/// first time it was called. However, we arrange to have it called during the
+/// startup of the process to get approximately correct results.
+static TimeValue getElapsedWallTime() {
+ static TimeValue &StartTime = *new TimeValue(TimeValue::now());
+ return TimeValue::now() - StartTime;
+}
+
+/// \brief A special global variable to ensure we call \c getElapsedWallTime
+/// during global initialization of the program.
+///
+/// Note that this variable is never referenced elsewhere. Doing so could
+/// create race conditions during program startup or shutdown.
+static volatile TimeValue DummyTimeValue = getElapsedWallTime();
+
+// Implement this routine by using the static helpers above. They're already
+// portable.
+TimeValue self_process::get_wall_time() const {
+ return getElapsedWallTime();
+}
+
+
+#if defined(_MSC_VER)
+#pragma warning(pop)
+#endif
+
+
// Include the platform-specific parts of this class.
#ifdef LLVM_ON_UNIX
#include "Unix/Process.inc"