Add support for compiling varargs functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6325 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/SparcV9/SparcV9InstrSelection.cpp b/lib/Target/SparcV9/SparcV9InstrSelection.cpp
index 61a8045..709c338 100644
--- a/lib/Target/SparcV9/SparcV9InstrSelection.cpp
+++ b/lib/Target/SparcV9/SparcV9InstrSelection.cpp
@@ -22,6 +22,7 @@
#include "llvm/Function.h"
#include "llvm/Constants.h"
#include "llvm/ConstantHandling.h"
+#include "llvm/Intrinsics.h"
#include "Support/MathExtras.h"
#include <math.h>
@@ -1298,6 +1299,46 @@
return true;
}
+// Generate code for any intrinsic that needs a special code sequence
+// instead of a regular call. If not that kind of intrinsic, do nothing.
+// Returns true if code was generated, otherwise false.
+//
+bool CodeGenIntrinsic(LLVMIntrinsic::ID iid, CallInst &callInstr,
+ TargetMachine &target,
+ std::vector<MachineInstr*>& mvec)
+{
+ switch (iid) {
+ case LLVMIntrinsic::va_start: {
+ // Get the address of the first vararg value on stack and copy it to
+ // the argument of va_start(va_list* ap).
+ bool ignore;
+ Function* func = cast<Function>(callInstr.getParent()->getParent());
+ int numFixedArgs = func->getFunctionType()->getNumParams();
+ int fpReg = target.getFrameInfo().getIncomingArgBaseRegNum();
+ int argSize = target.getFrameInfo().getSizeOfEachArgOnStack();
+ int firstVarArgOff = numFixedArgs * argSize + target.getFrameInfo().
+ getFirstIncomingArgOffset(MachineFunction::get(func), ignore);
+ mvec.push_back(BuildMI(V9::ADD, 3).addMReg(fpReg).addSImm(firstVarArgOff).
+ addReg(callInstr.getOperand(1)));
+ return true;
+ }
+
+ case LLVMIntrinsic::va_end:
+ return true; // no-op on Sparc
+
+ case LLVMIntrinsic::va_copy:
+ // Simple copy of current va_list (arg2) to new va_list (arg1)
+ mvec.push_back(BuildMI(V9::OR, 3).
+ addMReg(target.getRegInfo().getZeroRegNum()).
+ addReg(callInstr.getOperand(2)).
+ addReg(callInstr.getOperand(1)));
+ return true;
+
+ default:
+ return false;
+ }
+}
+
//******************* Externally Visible Functions *************************/
//------------------------------------------------------------------------
@@ -2101,96 +2142,112 @@
//
CallInst *callInstr = cast<CallInst>(subtreeRoot->getInstruction());
Value *callee = callInstr->getCalledValue();
+ Function* calledFunc = dyn_cast<Function>(callee);
- // Create hidden virtual register for return address with type void*
- TmpInstruction* retAddrReg =
- new TmpInstruction(PointerType::get(Type::VoidTy), callInstr);
- MachineCodeForInstruction::get(callInstr).addTemp(retAddrReg);
-
- // Generate the machine instruction and its operands.
- // Use CALL for direct function calls; this optimistically assumes
- // the PC-relative address fits in the CALL address field (22 bits).
- // Use JMPL for indirect calls.
+ // Check if this is an intrinsic function that needs a special code
+ // sequence (e.g., va_start). Indirect calls cannot be special.
//
- if (isa<Function>(callee)) // direct function call
- M = BuildMI(V9::CALL, 1).addPCDisp(callee);
- else // indirect function call
- M = BuildMI(V9::JMPLCALL, 3).addReg(callee).addSImm((int64_t)0)
- .addRegDef(retAddrReg);
- mvec.push_back(M);
+ bool specialIntrinsic = false;
+ LLVMIntrinsic::ID iid;
+ if (calledFunc && (iid=(LLVMIntrinsic::ID)calledFunc->getIntrinsicID()))
+ specialIntrinsic = CodeGenIntrinsic(iid, *callInstr, target, mvec);
- const FunctionType* funcType =
- cast<FunctionType>(cast<PointerType>(callee->getType())
- ->getElementType());
- bool isVarArgs = funcType->isVarArg();
- bool noPrototype = isVarArgs && funcType->getNumParams() == 0;
-
- // Use a descriptor to pass information about call arguments
- // to the register allocator. This descriptor will be "owned"
- // and freed automatically when the MachineCodeForInstruction
- // object for the callInstr goes away.
- CallArgsDescriptor* argDesc = new CallArgsDescriptor(callInstr,
- retAddrReg, isVarArgs, noPrototype);
-
- assert(callInstr->getOperand(0) == callee
- && "This is assumed in the loop below!");
-
- for (unsigned i=1, N=callInstr->getNumOperands(); i < N; ++i)
+ // If not, generate the normal call sequence for the function.
+ // This can also handle any intrinsics that are just function calls.
+ //
+ if (! specialIntrinsic)
{
- Value* argVal = callInstr->getOperand(i);
- Instruction* intArgReg = NULL;
+ // Create hidden virtual register for return address with type void*
+ TmpInstruction* retAddrReg =
+ new TmpInstruction(PointerType::get(Type::VoidTy), callInstr);
+ MachineCodeForInstruction::get(callInstr).addTemp(retAddrReg);
+
+ // Generate the machine instruction and its operands.
+ // Use CALL for direct function calls; this optimistically assumes
+ // the PC-relative address fits in the CALL address field (22 bits).
+ // Use JMPL for indirect calls.
+ //
+ if (calledFunc) // direct function call
+ M = BuildMI(V9::CALL, 1).addPCDisp(callee);
+ else // indirect function call
+ M = BuildMI(V9::JMPLCALL, 3).addReg(callee).addSImm((int64_t)0)
+ .addRegDef(retAddrReg);
+ mvec.push_back(M);
+
+ const FunctionType* funcType =
+ cast<FunctionType>(cast<PointerType>(callee->getType())
+ ->getElementType());
+ bool isVarArgs = funcType->isVarArg();
+ bool noPrototype = isVarArgs && funcType->getNumParams() == 0;
+
+ // Use a descriptor to pass information about call arguments
+ // to the register allocator. This descriptor will be "owned"
+ // and freed automatically when the MachineCodeForInstruction
+ // object for the callInstr goes away.
+ CallArgsDescriptor* argDesc = new CallArgsDescriptor(callInstr,
+ retAddrReg, isVarArgs,noPrototype);
- // Check for FP arguments to varargs functions.
- // Any such argument in the first $K$ args must be passed in an
- // integer register, where K = #integer argument registers.
- if (isVarArgs && argVal->getType()->isFloatingPoint())
+ assert(callInstr->getOperand(0) == callee
+ && "This is assumed in the loop below!");
+
+ for (unsigned i=1, N=callInstr->getNumOperands(); i < N; ++i)
{
- // If it is a function with no prototype, pass value
- // as an FP value as well as a varargs value
- if (noPrototype)
- argDesc->getArgInfo(i-1).setUseFPArgReg();
-
- // If this arg. is in the first $K$ regs, add a copy
- // float-to-int instruction to pass the value as an integer.
- if (i <= target.getRegInfo().GetNumOfIntArgRegs())
+ Value* argVal = callInstr->getOperand(i);
+ Instruction* intArgReg = NULL;
+
+ // Check for FP arguments to varargs functions.
+ // Any such argument in the first $K$ args must be passed in an
+ // integer register, where K = #integer argument registers.
+ if (isVarArgs && argVal->getType()->isFloatingPoint())
{
- MachineCodeForInstruction &destMCFI =
- MachineCodeForInstruction::get(callInstr);
- intArgReg = new TmpInstruction(Type::IntTy, argVal);
- destMCFI.addTemp(intArgReg);
+ // If it is a function with no prototype, pass value
+ // as an FP value as well as a varargs value
+ if (noPrototype)
+ argDesc->getArgInfo(i-1).setUseFPArgReg();
+
+ // If this arg. is in the first $K$ regs, add a copy
+ // float-to-int instruction to pass the value as an integer.
+ if (i <= target.getRegInfo().getNumOfIntArgRegs())
+ {
+ MachineCodeForInstruction &destMCFI =
+ MachineCodeForInstruction::get(callInstr);
+ intArgReg = new TmpInstruction(Type::IntTy, argVal);
+ destMCFI.addTemp(intArgReg);
- std::vector<MachineInstr*> copyMvec;
- target.getInstrInfo().CreateCodeToCopyFloatToInt(target,
- callInstr->getParent()->getParent(),
- argVal, (TmpInstruction*) intArgReg,
- copyMvec, destMCFI);
- mvec.insert(mvec.begin(),copyMvec.begin(),copyMvec.end());
+ std::vector<MachineInstr*> copyMvec;
+ target.getInstrInfo().CreateCodeToCopyFloatToInt(target,
+ callInstr->getParent()->getParent(),
+ argVal, (TmpInstruction*) intArgReg,
+ copyMvec, destMCFI);
+ mvec.insert(mvec.begin(),copyMvec.begin(),copyMvec.end());
- argDesc->getArgInfo(i-1).setUseIntArgReg();
- argDesc->getArgInfo(i-1).setArgCopy(intArgReg);
+ argDesc->getArgInfo(i-1).setUseIntArgReg();
+ argDesc->getArgInfo(i-1).setArgCopy(intArgReg);
+ }
+ else
+ // Cannot fit in first $K$ regs so pass arg on stack
+ argDesc->getArgInfo(i-1).setUseStackSlot();
}
- else
- // Cannot fit in first $K$ regs so pass the arg on the stack
- argDesc->getArgInfo(i-1).setUseStackSlot();
+
+ if (intArgReg)
+ mvec.back()->addImplicitRef(intArgReg);
+
+ mvec.back()->addImplicitRef(argVal);
}
-
- if (intArgReg)
- mvec.back()->addImplicitRef(intArgReg);
-
- mvec.back()->addImplicitRef(argVal);
+
+ // Add the return value as an implicit ref. The call operands
+ // were added above.
+ if (callInstr->getType() != Type::VoidTy)
+ mvec.back()->addImplicitRef(callInstr, /*isDef*/ true);
+
+ // For the CALL instruction, the ret. addr. reg. is also implicit
+ if (isa<Function>(callee))
+ mvec.back()->addImplicitRef(retAddrReg, /*isDef*/ true);
+
+ // delay slot
+ mvec.push_back(BuildMI(V9::NOP, 0));
}
-
- // Add the return value as an implicit ref. The call operands
- // were added above.
- if (callInstr->getType() != Type::VoidTy)
- mvec.back()->addImplicitRef(callInstr, /*isDef*/ true);
-
- // For the CALL instruction, the ret. addr. reg. is also implicit
- if (isa<Function>(callee))
- mvec.back()->addImplicitRef(retAddrReg, /*isDef*/ true);
-
- // delay slot
- mvec.push_back(BuildMI(V9::NOP, 0));
+
break;
}
@@ -2225,6 +2282,19 @@
case 64: // reg: Phi(reg,reg)
break; // don't forward the value
+ case 65: // reg: VaArg(reg)
+ {
+ // Use value initialized by va_start as pointer to args on the stack.
+ // Load argument via current pointer value, then increment pointer.
+ int argSize = target.getFrameInfo().getSizeOfEachArgOnStack();
+ Instruction* vaArgI = subtreeRoot->getInstruction();
+ mvec.push_back(BuildMI(V9::LDX, 3).addReg(vaArgI->getOperand(0)).
+ addSImm(0).addRegDef(vaArgI));
+ mvec.push_back(BuildMI(V9::ADD, 3).addReg(vaArgI->getOperand(0)).
+ addSImm(argSize).addRegDef(vaArgI->getOperand(0)));
+ break;
+ }
+
case 71: // reg: VReg
case 72: // reg: Constant
break; // don't forward the value