Rather than having special rules like "intrinsics cannot

throw exceptions", just mark intrinsics with the nounwind
attribute.  Likewise, mark intrinsics as readnone/readonly
and get rid of special aliasing logic (which didn't use
anything more than this anyway).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44544 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 57 insertions, 23 deletions

diff --git a/lib/VMCore/AutoUpgrade.cpp b/lib/VMCore/AutoUpgrade.cpp
index 40c431c..311941f 100644
--- a/lib/VMCore/AutoUpgrade.cpp
+++ b/lib/VMCore/AutoUpgrade.cpp
@@ -20,7 +20,7 @@
 using namespace llvm;
 
 
-Function* llvm::UpgradeIntrinsicFunction(Function *F) {
+static Function* UpgradeIntrinsicFunction1(Function *F) {
   assert(F && "Illegal to upgrade a non-existent Function.");
 
   // Get the Function's name.
@@ -119,6 +119,17 @@ Function* llvm::UpgradeIntrinsicFunction(Function *F) {
   return 0;
 }
 
+Function* llvm::UpgradeIntrinsicFunction(Function *F) {
+  Function *Upgraded = UpgradeIntrinsicFunction1(F);
+
+  // Upgrade intrinsic attributes.  This does not change the function.
+  if (Upgraded)
+    F = Upgraded;
+  if (unsigned id = F->getIntrinsicID(true))
+    F->setParamAttrs(Intrinsic::getParamAttrs((Intrinsic::ID)id));
+  return Upgraded;
+}
+
 // UpgradeIntrinsicCall - Upgrade a call to an old intrinsic to be a call the 
 // upgraded intrinsic. All argument and return casting must be provided in 
 // order to seamlessly integrate with existing context.
diff --git a/lib/VMCore/Function.cpp b/lib/VMCore/Function.cpp
index 3794955..04db3aa 100644
--- a/lib/VMCore/Function.cpp
+++ b/lib/VMCore/Function.cpp
@@ -18,6 +18,7 @@
 #include "llvm/Support/LeakDetector.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "SymbolTableListTraitsImpl.h"
+#include "llvm/ADT/BitVector.h"
 #include "llvm/ADT/StringExtras.h"
 using namespace llvm;
 
@@ -435,12 +436,36 @@ const FunctionType *Intrinsic::getType(ID id, const Type **Tys,
   return FunctionType::get(ResultTy, ArgTys, IsVarArg); 
 }
 
+const ParamAttrsList *Intrinsic::getParamAttrs(ID id) {
+  static const ParamAttrsList *IntrinsicAttributes[Intrinsic::num_intrinsics];
+
+  if (IntrinsicAttributes[id])
+    return IntrinsicAttributes[id];
+
+  ParamAttrsVector Attrs;
+  uint16_t Attr = ParamAttr::None;
+
+#define GET_INTRINSIC_ATTRIBUTES
+#include "llvm/Intrinsics.gen"
+#undef GET_INTRINSIC_ATTRIBUTES
+
+  // Intrinsics cannot throw exceptions.
+  Attr |= ParamAttr::NoUnwind;
+
+  Attrs.push_back(ParamAttrsWithIndex::get(0, Attr));
+  IntrinsicAttributes[id] = ParamAttrsList::get(Attrs);
+  return IntrinsicAttributes[id];
+}
+
 Function *Intrinsic::getDeclaration(Module *M, ID id, const Type **Tys, 
                                     unsigned numTys) {
-// There can never be multiple globals with the same name of different types,
-// because intrinsics must be a specific type.
-  return cast<Function>(M->getOrInsertFunction(getName(id, Tys, numTys), 
-                                               getType(id, Tys, numTys)));
+  // There can never be multiple globals with the same name of different types,
+  // because intrinsics must be a specific type.
+  Function *F =
+    cast<Function>(M->getOrInsertFunction(getName(id, Tys, numTys),
+                                          getType(id, Tys, numTys)));
+  F->setParamAttrs(getParamAttrs(id));
+  return F;
 }
 
 Value *IntrinsicInst::StripPointerCasts(Value *Ptr) {
diff --git a/lib/VMCore/Instruction.cpp b/lib/VMCore/Instruction.cpp
index a368753..9b20885 100644
--- a/lib/VMCore/Instruction.cpp
+++ b/lib/VMCore/Instruction.cpp
@@ -13,8 +13,8 @@
 
 #include "llvm/Type.h"
 #include "llvm/Instructions.h"
-#include "llvm/IntrinsicInst.h"
 #include "llvm/Function.h"
+#include "llvm/Support/CallSite.h"
 #include "llvm/Support/LeakDetector.h"
 using namespace llvm;
 
@@ -197,31 +197,18 @@ bool Instruction::isSameOperationAs(Instruction *I) const {
   return true;
 }
 
-// IntrinsicOnlyReadsMemory - Return true if the specified intrinsic doesn't
-// have any side-effects or if it only reads memory.
-static bool IntrinsicOnlyReadsMemory(unsigned IntrinsicID) {
-#define GET_SIDE_EFFECT_INFO
-#include "llvm/Intrinsics.gen"
-#undef GET_SIDE_EFFECT_INFO
-  return false;
-}
-
 /// mayWriteToMemory - Return true if this instruction may modify memory.
 ///
 bool Instruction::mayWriteToMemory() const {
   switch (getOpcode()) {
   default: return false;
   case Instruction::Free:
-  case Instruction::Store:
   case Instruction::Invoke:
+  case Instruction::Store:
   case Instruction::VAArg:
     return true;
   case Instruction::Call:
-    if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(this)) {
-      // If the intrinsic doesn't write memory, it is safe.
-      return !IntrinsicOnlyReadsMemory(II->getIntrinsicID());
-    }
-    return true;
+    return !cast<CallInst>(this)->onlyReadsMemory();
   case Instruction::Load:
     return cast<LoadInst>(this)->isVolatile();
   }
diff --git a/lib/VMCore/Instructions.cpp b/lib/VMCore/Instructions.cpp
index 7ad588c..0df0466 100644
--- a/lib/VMCore/Instructions.cpp
+++ b/lib/VMCore/Instructions.cpp
@@ -53,7 +53,18 @@ bool CallSite::paramHasAttr(uint16_t i, ParameterAttributes attr) const {
   else
     return cast<InvokeInst>(I)->paramHasAttr(i, attr);
 }
-
+bool CallSite::doesNotAccessMemory() const {
+  if (CallInst *CI = dyn_cast<CallInst>(I))
+    return CI->doesNotAccessMemory();
+  else
+    return cast<InvokeInst>(I)->doesNotAccessMemory();
+}
+bool CallSite::onlyReadsMemory() const {
+  if (CallInst *CI = dyn_cast<CallInst>(I))
+    return CI->onlyReadsMemory();
+  else
+    return cast<InvokeInst>(I)->onlyReadsMemory();
+}
 
 
 
diff --git a/lib/VMCore/Mangler.cpp b/lib/VMCore/Mangler.cpp
index 8b8ba59..8689c86 100644
--- a/lib/VMCore/Mangler.cpp
+++ b/lib/VMCore/Mangler.cpp
@@ -135,7 +135,7 @@ std::string Mangler::getValueName(const GlobalValue *GV, const char * Suffix) {
   // Name mangling occurs as follows:
   // - If V is an intrinsic function, do not change name at all
   // - Otherwise, mangling occurs if global collides with existing name.
-  if (isa<Function>(GV) && cast<Function>(GV)->getIntrinsicID()) {
+  if (isa<Function>(GV) && cast<Function>(GV)->isIntrinsic()) {
     Name = GV->getName(); // Is an intrinsic function
   } else if (!GV->hasName()) {
     // Must mangle the global into a unique ID.