--- /dev/null
+//===-- NVPTXLowerStructArgs.cpp - Copy struct args to local memory =====--===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Copy struct args to local memory. This is needed for kernel functions only.
+// This is a preparation for handling cases like
+//
+// kernel void foo(struct A arg, ...)
+// {
+// struct A *p = &arg;
+// ...
+// ... = p->filed1 ... (this is no generic address for .param)
+// p->filed2 = ... (this is no write access to .param)
+// }
+//
+//===----------------------------------------------------------------------===//
+
+#include "NVPTX.h"
+#include "NVPTXUtilities.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Pass.h"
+
+using namespace llvm;
+
+namespace llvm {
+void initializeNVPTXLowerStructArgsPass(PassRegistry &);
+}
+
+class LLVM_LIBRARY_VISIBILITY NVPTXLowerStructArgs : public FunctionPass {
+ bool runOnFunction(Function &F) override;
+
+ void handleStructPtrArgs(Function &);
+ void handleParam(Argument *);
+
+public:
+ static char ID; // Pass identification, replacement for typeid
+ NVPTXLowerStructArgs() : FunctionPass(ID) {}
+ const char *getPassName() const override {
+ return "Copy structure (byval *) arguments to stack";
+ }
+};
+
+char NVPTXLowerStructArgs::ID = 1;
+
+INITIALIZE_PASS(NVPTXLowerStructArgs, "nvptx-lower-struct-args",
+ "Lower structure arguments (NVPTX)", false, false)
+
+void NVPTXLowerStructArgs::handleParam(Argument *Arg) {
+ Function *Func = Arg->getParent();
+ Instruction *FirstInst = &(Func->getEntryBlock().front());
+ const PointerType *PType = dyn_cast<PointerType>(Arg->getType());
+
+ assert(PType && "Expecting pointer type in handleParam");
+
+ const Type *StructType = PType->getElementType();
+
+ AllocaInst *AllocA =
+ new AllocaInst((Type *)StructType, Arg->getName(), FirstInst);
+
+ /* Set the alignment to alignment of the byval parameter. This is because,
+ * later load/stores assume that alignment, and we are going to replace
+ * the use of the byval parameter with this alloca instruction.
+ */
+ AllocA->setAlignment(Func->getParamAlignment(Arg->getArgNo() + 1));
+
+ Arg->replaceAllUsesWith(AllocA);
+
+ // Get the cvt.gen.to.param intrinsic
+ const Type *CvtTypes[2] = {
+ Type::getInt8PtrTy(Func->getParent()->getContext(), ADDRESS_SPACE_PARAM),
+ Type::getInt8PtrTy(Func->getParent()->getContext(), ADDRESS_SPACE_GENERIC)
+ };
+ Function *CvtFunc = (Function *)Intrinsic::getDeclaration(
+ Func->getParent(), Intrinsic::nvvm_ptr_gen_to_param,
+ ArrayRef<Type *>((Type **)CvtTypes, 2));
+ std::vector<Value *> BC1;
+ BC1.push_back(
+ new BitCastInst(Arg, Type::getInt8PtrTy(Func->getParent()->getContext(),
+ ADDRESS_SPACE_GENERIC),
+ Arg->getName(), FirstInst));
+ CallInst *CallCVT = CallInst::Create(CvtFunc, ArrayRef<Value *>(BC1),
+ "cvt_to_param", FirstInst);
+
+ BitCastInst *BitCast = new BitCastInst(
+ CallCVT, PointerType::get((Type *)StructType, ADDRESS_SPACE_PARAM),
+ Arg->getName(), FirstInst);
+ LoadInst *LI = new LoadInst(BitCast, Arg->getName(), FirstInst);
+ new StoreInst(LI, AllocA, FirstInst);
+}
+
+/// =============================================================================
+/// If the function had a struct ptr arg, say foo(%struct.x *byval %d), then
+/// add the following instructions to the first basic block :
+///
+/// %temp = alloca %struct.x, align 8
+/// %tt1 = bitcast %struct.x * %d to i8 *
+/// %tt2 = llvm.nvvm.cvt.gen.to.param %tt2
+/// %tempd = bitcast i8 addrspace(101) * to %struct.x addrspace(101) *
+/// %tv = load %struct.x addrspace(101) * %tempd
+/// store %struct.x %tv, %struct.x * %temp, align 8
+///
+/// The above code allocates some space in the stack and copies the incoming
+/// struct from param space to local space.
+/// Then replace all occurences of %d by %temp.
+/// =============================================================================
+void NVPTXLowerStructArgs::handleStructPtrArgs(Function &F) {
+ const AttributeSet &PAL = F.getAttributes();
+
+ unsigned Idx = 1;
+
+ for (Argument &Arg : F.args()) {
+ const Type *Ty = Arg.getType();
+
+ const PointerType *PTy = dyn_cast<PointerType>(Ty);
+
+ if (PTy) {
+ if (PAL.hasAttribute(Idx, Attribute::ByVal)) {
+ // cout << "Has struct ptr args" << std::endl;
+ handleParam(&Arg);
+ }
+ }
+ Idx++;
+ }
+}
+
+/// =============================================================================
+/// Main function for this pass.
+/// =============================================================================
+bool NVPTXLowerStructArgs::runOnFunction(Function &F) {
+ // Skip non-kernels. See the comments at the top of this file.
+ if (!isKernelFunction(F))
+ return false;
+
+ handleStructPtrArgs(F);
+
+ return true;
+}
+
+FunctionPass *llvm::createNVPTXLowerStructArgsPass() {
+ return new NVPTXLowerStructArgs();
+}
--- /dev/null
+; RUN: opt < %s -nvptx-lower-struct-args -S | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v16:16:16-v32:32:32-v64:64:64-v128:128:128-n16:32:64"
+target triple = "nvptx64-unknown-unknown"
+
+%struct.S = type { i32, i32 }
+
+; Function Attrs: nounwind
+define void @_Z11TakesStruct1SPi(%struct.S* byval nocapture readonly %input, i32* nocapture %output) #0 {
+entry:
+; CHECK-LABEL @_Z22TakesStruct1SPi
+; CHECK: bitcast %struct.S* %input to i8*
+; CHECK: call i8 addrspace(101)* @llvm.nvvm.ptr.gen.to.param.p101i8.p0i8
+ %b = getelementptr inbounds %struct.S* %input, i64 0, i32 1
+ %0 = load i32* %b, align 4
+ store i32 %0, i32* %output, align 4
+ ret void
+}
+
+attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!nvvm.annotations = !{!0}
+
+!0 = metadata !{void (%struct.S*, i32*)* @_Z11TakesStruct1SPi, metadata !"kernel", i32 1}
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