-//===- FunctionAttrs.cpp - Pass which marks functions readnone or readonly ===//
+//===- FunctionAttrs.cpp - Pass which marks functions attributes ----------===//
//
// The LLVM Compiler Infrastructure
//
// to the function does not create any copies of the pointer value that
// outlive the call. This more or less means that the pointer is only
// dereferenced, and not returned from the function or stored in a global.
+// Finally, well-known library call declarations are marked with all
+// attributes that are consistent with the function's standard definition.
// This pass is implemented as a bottom-up traversal of the call-graph.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "functionattrs"
#include "llvm/Transforms/IPO.h"
-#include "llvm/CallGraphSCCPass.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/LLVMContext.h"
-#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/CallGraph.h"
-#include "llvm/Analysis/CaptureTracking.h"
#include "llvm/ADT/SCCIterator.h"
+#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/UniqueVector.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/CallGraph.h"
+#include "llvm/Analysis/CallGraphSCCPass.h"
+#include "llvm/Analysis/CaptureTracking.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/InstIterator.h"
+#include "llvm/Target/TargetLibraryInfo.h"
using namespace llvm;
STATISTIC(NumReadNone, "Number of functions marked readnone");
STATISTIC(NumReadOnly, "Number of functions marked readonly");
STATISTIC(NumNoCapture, "Number of arguments marked nocapture");
STATISTIC(NumNoAlias, "Number of function returns marked noalias");
+STATISTIC(NumAnnotated, "Number of attributes added to library functions");
namespace {
struct FunctionAttrs : public CallGraphSCCPass {
// AddNoAliasAttrs - Deduce noalias attributes for the SCC.
bool AddNoAliasAttrs(const CallGraphSCC &SCC);
+ // Utility methods used by inferPrototypeAttributes to add attributes
+ // and maintain annotation statistics.
+
+ void setDoesNotAccessMemory(Function &F) {
+ if (!F.doesNotAccessMemory()) {
+ F.setDoesNotAccessMemory();
+ ++NumAnnotated;
+ }
+ }
+
+ void setOnlyReadsMemory(Function &F) {
+ if (!F.onlyReadsMemory()) {
+ F.setOnlyReadsMemory();
+ ++NumAnnotated;
+ }
+ }
+
+ void setDoesNotThrow(Function &F) {
+ if (!F.doesNotThrow()) {
+ F.setDoesNotThrow();
+ ++NumAnnotated;
+ }
+ }
+
+ void setDoesNotCapture(Function &F, unsigned n) {
+ if (!F.doesNotCapture(n)) {
+ F.setDoesNotCapture(n);
+ ++NumAnnotated;
+ }
+ }
+
+ void setDoesNotAlias(Function &F, unsigned n) {
+ if (!F.doesNotAlias(n)) {
+ F.setDoesNotAlias(n);
+ ++NumAnnotated;
+ }
+ }
+
+ // inferPrototypeAttributes - Analyze the name and prototype of the
+ // given function and set any applicable attributes. Returns true
+ // if any attributes were set and false otherwise.
+ bool inferPrototypeAttributes(Function &F);
+
+ // annotateLibraryCalls - Adds attributes to well-known standard library
+ // call declarations.
+ bool annotateLibraryCalls(const CallGraphSCC &SCC);
+
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
AU.addRequired<AliasAnalysis>();
+ AU.addRequired<TargetLibraryInfo>();
CallGraphSCCPass::getAnalysisUsage(AU);
}
private:
AliasAnalysis *AA;
+ TargetLibraryInfo *TLI;
};
}
INITIALIZE_PASS_BEGIN(FunctionAttrs, "functionattrs",
"Deduce function attributes", false, false)
INITIALIZE_AG_DEPENDENCY(CallGraph)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfo)
INITIALIZE_PASS_END(FunctionAttrs, "functionattrs",
"Deduce function attributes", false, false)
MadeChange = true;
// Clear out any existing attributes.
- F->removeAttribute(~0, Attribute::ReadOnly | Attribute::ReadNone);
+ AttrBuilder B;
+ B.addAttribute(Attribute::ReadOnly)
+ .addAttribute(Attribute::ReadNone);
+ F->removeAttributes(AttributeSet::FunctionIndex,
+ AttributeSet::get(F->getContext(),
+ AttributeSet::FunctionIndex, B));
// Add in the new attribute.
- F->addAttribute(~0, ReadsMemory? Attribute::ReadOnly : Attribute::ReadNone);
+ F->addAttribute(AttributeSet::FunctionIndex,
+ ReadsMemory ? Attribute::ReadOnly : Attribute::ReadNone);
if (ReadsMemory)
++NumReadOnly;
void tooManyUses() { Captured = true; }
- bool shouldExplore(Use *U) { return true; }
-
bool captured(Use *U) {
CallSite CS(U->getUser());
if (!CS.getInstruction()) { Captured = true; return true; }
ArgumentGraph AG;
+ AttrBuilder B;
+ B.addAttribute(Attribute::NoCapture);
+
// Check each function in turn, determining which pointer arguments are not
// captured.
for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) {
for (Function::arg_iterator A = F->arg_begin(), E = F->arg_end();
A != E; ++A) {
if (A->getType()->isPointerTy() && !A->hasNoCaptureAttr()) {
- A->addAttr(Attribute::NoCapture);
+ A->addAttr(AttributeSet::get(F->getContext(), A->getArgNo() + 1, B));
++NumNoCapture;
Changed = true;
}
if (!Tracker.Captured) {
if (Tracker.Uses.empty()) {
// If it's trivially not captured, mark it nocapture now.
- A->addAttr(Attribute::NoCapture);
+ A->addAttr(AttributeSet::get(F->getContext(), A->getArgNo()+1, B));
++NumNoCapture;
Changed = true;
} else {
// eg. "void f(int* x) { if (...) f(x); }"
if (ArgumentSCC[0]->Uses.size() == 1 &&
ArgumentSCC[0]->Uses[0] == ArgumentSCC[0]) {
- ArgumentSCC[0]->Definition->addAttr(Attribute::NoCapture);
+ ArgumentSCC[0]->
+ Definition->
+ addAttr(AttributeSet::get(ArgumentSCC[0]->Definition->getContext(),
+ ArgumentSCC[0]->Definition->getArgNo() + 1,
+ B));
++NumNoCapture;
Changed = true;
}
for (unsigned i = 0, e = ArgumentSCC.size(); i != e; ++i) {
Argument *A = ArgumentSCC[i]->Definition;
- A->addAttr(Attribute::NoCapture);
+ A->addAttr(AttributeSet::get(A->getContext(), A->getArgNo() + 1, B));
++NumNoCapture;
Changed = true;
}
/// or a pointer that doesn't alias any other pointer visible to the caller.
bool FunctionAttrs::IsFunctionMallocLike(Function *F,
SmallPtrSet<Function*, 8> &SCCNodes) const {
- UniqueVector<Value *> FlowsToReturn;
+ SmallSetVector<Value *, 8> FlowsToReturn;
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I)
if (ReturnInst *Ret = dyn_cast<ReturnInst>(I->getTerminator()))
FlowsToReturn.insert(Ret->getReturnValue());
for (unsigned i = 0; i != FlowsToReturn.size(); ++i) {
- Value *RetVal = FlowsToReturn[i+1]; // UniqueVector[0] is reserved.
+ Value *RetVal = FlowsToReturn[i];
if (Constant *C = dyn_cast<Constant>(RetVal)) {
if (!C->isNullValue() && !isa<UndefValue>(C))
case Instruction::Call:
case Instruction::Invoke: {
CallSite CS(RVI);
- if (CS.paramHasNoAliasAttr(0))
+ if (CS.paramHasAttr(0, Attribute::NoAlias))
break;
if (CS.getCalledFunction() &&
SCCNodes.count(CS.getCalledFunction()))
return MadeChange;
}
+/// inferPrototypeAttributes - Analyze the name and prototype of the
+/// given function and set any applicable attributes. Returns true
+/// if any attributes were set and false otherwise.
+bool FunctionAttrs::inferPrototypeAttributes(Function &F) {
+ FunctionType *FTy = F.getFunctionType();
+ LibFunc::Func TheLibFunc;
+ if (!(TLI->getLibFunc(F.getName(), TheLibFunc) && TLI->has(TheLibFunc)))
+ return false;
+
+ switch (TheLibFunc) {
+ case LibFunc::strlen:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::strchr:
+ case LibFunc::strrchr:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isIntegerTy())
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ break;
+ case LibFunc::strcpy:
+ case LibFunc::stpcpy:
+ case LibFunc::strcat:
+ case LibFunc::strtol:
+ case LibFunc::strtod:
+ case LibFunc::strtof:
+ case LibFunc::strtoul:
+ case LibFunc::strtoll:
+ case LibFunc::strtold:
+ case LibFunc::strncat:
+ case LibFunc::strncpy:
+ case LibFunc::stpncpy:
+ case LibFunc::strtoull:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::strxfrm:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::strcmp:
+ case LibFunc::strspn:
+ case LibFunc::strncmp:
+ case LibFunc::strcspn:
+ case LibFunc::strcoll:
+ case LibFunc::strcasecmp:
+ case LibFunc::strncasecmp:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::strstr:
+ case LibFunc::strpbrk:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::strtok:
+ case LibFunc::strtok_r:
+ if (FTy->getNumParams() < 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::scanf:
+ case LibFunc::setbuf:
+ case LibFunc::setvbuf:
+ if (FTy->getNumParams() < 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::strdup:
+ case LibFunc::strndup:
+ if (FTy->getNumParams() < 1 || !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::stat:
+ case LibFunc::sscanf:
+ case LibFunc::sprintf:
+ case LibFunc::statvfs:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::snprintf:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(2)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 3);
+ break;
+ case LibFunc::setitimer:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(1)->isPointerTy() ||
+ !FTy->getParamType(2)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ setDoesNotCapture(F, 3);
+ break;
+ case LibFunc::system:
+ if (FTy->getNumParams() != 1 ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ // May throw; "system" is a valid pthread cancellation point.
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::malloc:
+ if (FTy->getNumParams() != 1 ||
+ !FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::memcmp:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::memchr:
+ case LibFunc::memrchr:
+ if (FTy->getNumParams() != 3)
+ return false;
+ setOnlyReadsMemory(F);
+ setDoesNotThrow(F);
+ break;
+ case LibFunc::modf:
+ case LibFunc::modff:
+ case LibFunc::modfl:
+ case LibFunc::memcpy:
+ case LibFunc::memccpy:
+ case LibFunc::memmove:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::memalign:
+ if (!FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::mkdir:
+ case LibFunc::mktime:
+ if (FTy->getNumParams() == 0 ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::realloc:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::read:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ // May throw; "read" is a valid pthread cancellation point.
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::rmdir:
+ case LibFunc::rewind:
+ case LibFunc::remove:
+ case LibFunc::realpath:
+ if (FTy->getNumParams() < 1 ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::rename:
+ case LibFunc::readlink:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::write:
+ if (FTy->getNumParams() != 3 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ // May throw; "write" is a valid pthread cancellation point.
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::bcopy:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::bcmp:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setOnlyReadsMemory(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::bzero:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::calloc:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::chmod:
+ case LibFunc::chown:
+ case LibFunc::ctermid:
+ case LibFunc::clearerr:
+ case LibFunc::closedir:
+ if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::atoi:
+ case LibFunc::atol:
+ case LibFunc::atof:
+ case LibFunc::atoll:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setOnlyReadsMemory(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::access:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::fopen:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::fdopen:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::feof:
+ case LibFunc::free:
+ case LibFunc::fseek:
+ case LibFunc::ftell:
+ case LibFunc::fgetc:
+ case LibFunc::fseeko:
+ case LibFunc::ftello:
+ case LibFunc::fileno:
+ case LibFunc::fflush:
+ case LibFunc::fclose:
+ case LibFunc::fsetpos:
+ case LibFunc::flockfile:
+ case LibFunc::funlockfile:
+ case LibFunc::ftrylockfile:
+ if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::ferror:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setOnlyReadsMemory(F);
+ break;
+ case LibFunc::fputc:
+ case LibFunc::fstat:
+ case LibFunc::frexp:
+ case LibFunc::frexpf:
+ case LibFunc::frexpl:
+ case LibFunc::fstatvfs:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::fgets:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(2)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 3);
+ case LibFunc::fread:
+ case LibFunc::fwrite:
+ if (FTy->getNumParams() != 4 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(3)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 4);
+ case LibFunc::fputs:
+ case LibFunc::fscanf:
+ case LibFunc::fprintf:
+ case LibFunc::fgetpos:
+ if (FTy->getNumParams() < 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::getc:
+ case LibFunc::getlogin_r:
+ case LibFunc::getc_unlocked:
+ if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::getenv:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setOnlyReadsMemory(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::gets:
+ case LibFunc::getchar:
+ setDoesNotThrow(F);
+ break;
+ case LibFunc::getitimer:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::getpwnam:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::ungetc:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::uname:
+ case LibFunc::unlink:
+ case LibFunc::unsetenv:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::utime:
+ case LibFunc::utimes:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::putc:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::puts:
+ case LibFunc::printf:
+ case LibFunc::perror:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::pread:
+ case LibFunc::pwrite:
+ if (FTy->getNumParams() != 4 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ // May throw; these are valid pthread cancellation points.
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::putchar:
+ setDoesNotThrow(F);
+ break;
+ case LibFunc::popen:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::pclose:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::vscanf:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::vsscanf:
+ case LibFunc::vfscanf:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(1)->isPointerTy() ||
+ !FTy->getParamType(2)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::valloc:
+ if (!FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::vprintf:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::vfprintf:
+ case LibFunc::vsprintf:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::vsnprintf:
+ if (FTy->getNumParams() != 4 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(2)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 3);
+ break;
+ case LibFunc::open:
+ if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ // May throw; "open" is a valid pthread cancellation point.
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::opendir:
+ if (FTy->getNumParams() != 1 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::tmpfile:
+ if (!FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::times:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::htonl:
+ case LibFunc::htons:
+ case LibFunc::ntohl:
+ case LibFunc::ntohs:
+ setDoesNotThrow(F);
+ setDoesNotAccessMemory(F);
+ break;
+ case LibFunc::lstat:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::lchown:
+ if (FTy->getNumParams() != 3 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::qsort:
+ if (FTy->getNumParams() != 4 || !FTy->getParamType(3)->isPointerTy())
+ return false;
+ // May throw; places call through function pointer.
+ setDoesNotCapture(F, 4);
+ break;
+ case LibFunc::dunder_strdup:
+ case LibFunc::dunder_strndup:
+ if (FTy->getNumParams() < 1 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::dunder_strtok_r:
+ if (FTy->getNumParams() != 3 ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::under_IO_getc:
+ if (FTy->getNumParams() != 1 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::under_IO_putc:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::dunder_isoc99_scanf:
+ if (FTy->getNumParams() < 1 ||
+ !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::stat64:
+ case LibFunc::lstat64:
+ case LibFunc::statvfs64:
+ case LibFunc::dunder_isoc99_sscanf:
+ if (FTy->getNumParams() < 1 ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::fopen64:
+ if (FTy->getNumParams() != 2 ||
+ !FTy->getReturnType()->isPointerTy() ||
+ !FTy->getParamType(0)->isPointerTy() ||
+ !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ setDoesNotCapture(F, 1);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::fseeko64:
+ case LibFunc::ftello64:
+ if (FTy->getNumParams() == 0 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 1);
+ break;
+ case LibFunc::tmpfile64:
+ if (!FTy->getReturnType()->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotAlias(F, 0);
+ break;
+ case LibFunc::fstat64:
+ case LibFunc::fstatvfs64:
+ if (FTy->getNumParams() != 2 || !FTy->getParamType(1)->isPointerTy())
+ return false;
+ setDoesNotThrow(F);
+ setDoesNotCapture(F, 2);
+ break;
+ case LibFunc::open64:
+ if (FTy->getNumParams() < 2 || !FTy->getParamType(0)->isPointerTy())
+ return false;
+ // May throw; "open" is a valid pthread cancellation point.
+ setDoesNotCapture(F, 1);
+ break;
+ default:
+ // Didn't mark any attributes.
+ return false;
+ }
+
+ return true;
+}
+
+/// annotateLibraryCalls - Adds attributes to well-known standard library
+/// call declarations.
+bool FunctionAttrs::annotateLibraryCalls(const CallGraphSCC &SCC) {
+ bool MadeChange = false;
+
+ // Check each function in turn annotating well-known library function
+ // declarations with attributes.
+ for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) {
+ Function *F = (*I)->getFunction();
+
+ if (F != 0 && F->isDeclaration())
+ MadeChange |= inferPrototypeAttributes(*F);
+ }
+
+ return MadeChange;
+}
+
bool FunctionAttrs::runOnSCC(CallGraphSCC &SCC) {
AA = &getAnalysis<AliasAnalysis>();
+ TLI = &getAnalysis<TargetLibraryInfo>();
- bool Changed = AddReadAttrs(SCC);
+ bool Changed = annotateLibraryCalls(SCC);
+ Changed |= AddReadAttrs(SCC);
Changed |= AddNoCaptureAttrs(SCC);
Changed |= AddNoAliasAttrs(SCC);
return Changed;