Try again at implementing thread-safe lazy pass initialization, without depending on static local initialization

being threadsafe AND ensuring that initialization is complete by the time the initializeFooPass method returns.

llvm-svn: 116492
This commit is contained in:
Owen Anderson 2010-10-14 17:59:03 +00:00
parent a1cc6ec3fb
commit afb95571d0
1 changed files with 72 additions and 10 deletions

View File

@ -24,7 +24,7 @@
#include "Pass.h"
#include "llvm/PassRegistry.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Compiler.h"
#include "llvm/System/Atomic.h"
#include <vector>
namespace llvm {
@ -137,8 +137,20 @@ private:
return PI; \
} \
void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
ATTRIBUTE_USED \
static void* initialized = initialize##passName##PassOnce(Registry); \
static volatile sys::cas_flag initialized = 0; \
sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
if (old_val == 0) { \
initialize##passName##PassOnce(Registry); \
sys::MemoryFence(); \
initialized = 2; \
} else { \
sys::cas_flag tmp = initialized; \
sys::MemoryFence(); \
while (tmp != 2) { \
tmp = initialized; \
sys::MemoryFence(); \
} \
} \
} \
static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis);
@ -157,8 +169,20 @@ private:
return PI; \
} \
void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
ATTRIBUTE_USED \
static void* initialized = initialize##passName##PassOnce(Registry); \
static volatile sys::cas_flag initialized = 0; \
sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
if (old_val == 0) { \
initialize##passName##PassOnce(Registry); \
sys::MemoryFence(); \
initialized = 2; \
} else { \
sys::cas_flag tmp = initialized; \
sys::MemoryFence(); \
while (tmp != 2) { \
tmp = initialized; \
sys::MemoryFence(); \
} \
} \
} \
static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis);
@ -244,11 +268,24 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
return AI; \
} \
void llvm::initialize##agName##AnalysisGroup(PassRegistry &Registry) { \
ATTRIBUTE_USED static void* initialized = \
static volatile sys::cas_flag initialized = 0; \
sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
if (old_val == 0) { \
initialize##agName##AnalysisGroupOnce(Registry); \
sys::MemoryFence(); \
initialized = 2; \
} else { \
sys::cas_flag tmp = initialized; \
sys::MemoryFence(); \
while (tmp != 2) { \
tmp = initialized; \
sys::MemoryFence(); \
} \
} \
} \
static RegisterAnalysisGroup<agName> agName##_info (name);
#define INITIALIZE_AG_PASS(passName, agName, arg, name, cfg, analysis, def) \
static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
PassInfo *PI = new PassInfo(name, arg, & passName ::ID, \
@ -260,12 +297,25 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
return AI; \
} \
void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
ATTRIBUTE_USED \
static void* initialized = initialize##passName##PassOnce(Registry); \
static volatile sys::cas_flag initialized = 0; \
sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
if (old_val == 0) { \
initialize##passName##PassOnce(Registry); \
sys::MemoryFence(); \
initialized = 2; \
} else { \
sys::cas_flag tmp = initialized; \
sys::MemoryFence(); \
while (tmp != 2) { \
tmp = initialized; \
sys::MemoryFence(); \
} \
} \
} \
static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis); \
static RegisterAnalysisGroup<agName, def> passName ## _ag(passName ## _info);
#define INITIALIZE_AG_PASS_BEGIN(passName, agName, arg, n, cfg, analysis, def) \
static void* initialize##passName##PassOnce(PassRegistry &Registry) {
@ -279,8 +329,20 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
return AI; \
} \
void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
ATTRIBUTE_USED \
static void* initialized = initialize##passName##PassOnce(Registry); \
static volatile sys::cas_flag initialized = 0; \
sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
if (old_val == 0) { \
initialize##passName##PassOnce(Registry); \
sys::MemoryFence(); \
initialized = 2; \
} else { \
sys::cas_flag tmp = initialized; \
sys::MemoryFence(); \
while (tmp != 2) { \
tmp = initialized; \
sys::MemoryFence(); \
} \
} \
} \
static RegisterPass<passName> passName ## _info(arg, n, cfg, analysis); \
static RegisterAnalysisGroup<agName, def> passName ## _ag(passName ## _info);