core changes for varargs
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22254 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Bytecode/Reader/ReaderWrappers.cpp b/lib/Bytecode/Reader/ReaderWrappers.cpp
index 6823936..8d1f384 100644
--- a/lib/Bytecode/Reader/ReaderWrappers.cpp
+++ b/lib/Bytecode/Reader/ReaderWrappers.cpp
@@ -149,6 +149,100 @@
}
//===----------------------------------------------------------------------===//
+// Varargs transmogrification code...
+//
+
+// CheckVarargs - This is used to automatically translate old-style varargs to
+// new style varargs for backwards compatibility.
+static ModuleProvider* CheckVarargs(ModuleProvider* MP) {
+ Module* M = MP->getModule();
+
+ // check to see if va_start takes arguements...
+ Function* F = M->getNamedFunction("llvm.va_start");
+ if(F == 0) return MP; //No varargs use, just return.
+
+ if (F->getFunctionType()->getNumParams() == 1)
+ return MP; // Modern varargs processing, just return.
+
+ // If we get to this point, we know that we have an old-style module.
+ // Materialize the whole thing to perform the rewriting.
+ MP->materializeModule();
+
+ if(Function* F = M->getNamedFunction("llvm.va_start")) {
+ assert(F->arg_size() == 0 && "Obsolete va_start takes 0 argument!");
+
+ //foo = va_start()
+ // ->
+ //bar = alloca typeof(foo)
+ //va_start(bar)
+ //foo = load bar
+
+ const Type* RetTy = Type::getPrimitiveType(Type::VoidTyID);
+ const Type* ArgTy = F->getFunctionType()->getReturnType();
+ const Type* ArgTyPtr = PointerType::get(ArgTy);
+ Function* NF = M->getOrInsertFunction("llvm.va_start",
+ RetTy, ArgTyPtr, 0);
+
+ for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
+ if (CallInst* CI = dyn_cast<CallInst>(*I++)) {
+ AllocaInst* bar = new AllocaInst(ArgTy, 0, "vastart.fix.1", CI);
+ new CallInst(NF, bar, "", CI);
+ Value* foo = new LoadInst(bar, "vastart.fix.2", CI);
+ CI->replaceAllUsesWith(foo);
+ CI->getParent()->getInstList().erase(CI);
+ }
+ F->setName("");
+ }
+
+ if(Function* F = M->getNamedFunction("llvm.va_end")) {
+ assert(F->arg_size() == 1 && "Obsolete va_end takes 1 argument!");
+ //vaend foo
+ // ->
+ //bar = alloca 1 of typeof(foo)
+ //vaend bar
+ const Type* RetTy = Type::getPrimitiveType(Type::VoidTyID);
+ const Type* ArgTy = F->getFunctionType()->getParamType(0);
+ const Type* ArgTyPtr = PointerType::get(ArgTy);
+ Function* NF = M->getOrInsertFunction("llvm.va_end",
+ RetTy, ArgTyPtr, 0);
+
+ for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
+ if (CallInst* CI = dyn_cast<CallInst>(*I++)) {
+ AllocaInst* bar = new AllocaInst(ArgTy, 0, "vaend.fix.1", CI);
+ new CallInst(NF, bar, "", CI);
+ CI->getParent()->getInstList().erase(CI);
+ }
+ F->setName("");
+ }
+
+ if(Function* F = M->getNamedFunction("llvm.va_copy")) {
+ assert(F->arg_size() == 1 && "Obsolete va_copy takes 1 argument!");
+ //foo = vacopy(bar)
+ // ->
+ //a = alloca 1 of typeof(foo)
+ //vacopy(a, bar)
+ //foo = load a
+
+ const Type* RetTy = Type::getPrimitiveType(Type::VoidTyID);
+ const Type* ArgTy = F->getFunctionType()->getReturnType();
+ const Type* ArgTyPtr = PointerType::get(ArgTy);
+ Function* NF = M->getOrInsertFunction("llvm.va_copy",
+ RetTy, ArgTyPtr, ArgTy, 0);
+
+ for(Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E;)
+ if (CallInst* CI = dyn_cast<CallInst>(*I++)) {
+ AllocaInst* a = new AllocaInst(ArgTy, 0, "vacopy.fix.1", CI);
+ new CallInst(NF, a, CI->getOperand(1), "", CI);
+ Value* foo = new LoadInst(a, "vacopy.fix.2", CI);
+ CI->replaceAllUsesWith(foo);
+ CI->getParent()->getInstList().erase(CI);
+ }
+ F->setName("");
+ }
+ return MP;
+}
+
+//===----------------------------------------------------------------------===//
// Wrapper functions
//===----------------------------------------------------------------------===//
@@ -159,7 +253,8 @@
unsigned Length,
const std::string &ModuleID,
BytecodeHandler* H ) {
- return new BytecodeBufferReader(Buffer, Length, ModuleID, H);
+ return CheckVarargs(
+ new BytecodeBufferReader(Buffer, Length, ModuleID, H));
}
/// ParseBytecodeBuffer - Parse a given bytecode buffer
@@ -182,9 +277,9 @@
ModuleProvider *llvm::getBytecodeModuleProvider(const std::string &Filename,
BytecodeHandler* H) {
if (Filename != std::string("-")) // Read from a file...
- return new BytecodeFileReader(Filename,H);
+ return CheckVarargs(new BytecodeFileReader(Filename,H));
else // Read from stdin
- return new BytecodeStdinReader(H);
+ return CheckVarargs(new BytecodeStdinReader(H));
}
/// ParseBytecodeFile - Parse the given bytecode file