From 91d6c8a987516b27bb9a08a352386191bf4bd9d7 Mon Sep 17 00:00:00 2001
From: Akash Kothari <akashk4@tyler.cs.illinois.edu>
Date: Fri, 17 Jan 2020 12:34:07 -0600
Subject: [PATCH] Added bug fixes to DFG2LLVM_X86 pass
---
.../Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp | 60 +++++++++++++++++--
1 file changed, 54 insertions(+), 6 deletions(-)
diff --git a/hpvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp b/hpvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp
index fb16c28c13..06e4e79183 100644
--- a/hpvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp
+++ b/hpvm/lib/Transforms/DFG2LLVM_X86/DFG2LLVM_X86.cpp
@@ -827,12 +827,60 @@ void CGT_X86::codeGenLaunch(DFInternalNode* Root) {
switchToTimer(visc_TimerID_COMPUTATION, CI);
switchToTimer(visc_TimerID_OUTPUT_PACK, RI);
- // Code for returning the output
- CastInst* OutputAddrCast = CastInst::CreatePointerCast(data,
- CI->getType()->getPointerTo(),
- CI->getName()+".addr",
- RI);
- new StoreInst(CI, OutputAddrCast, RI);
+ StructType *RootRetTy = cast<StructType>(RootF_X86->getFunctionType()->getReturnType());
+
+ // if Root has non empty return
+ if (RootRetTy->getNumElements()) {
+ // We can't access the type of the arg struct - build it
+ std::vector<Type*> TyList;
+ for(Function::arg_iterator ai = RootF_X86->arg_begin(), ae = RootF_X86->arg_end();
+ ai != ae; ++ai) {
+ TyList.push_back(ai->getType());
+ }
+ TyList.push_back(CI->getType());
+
+ StructType* ArgStructTy = StructType::create(M.getContext(),
+ ArrayRef<Type*>(TyList),
+ (RootF_X86->getName()+".arg.struct.ty").str(), true);
+
+ // Cast the data pointer to the type of the arg struct
+ CastInst* OutputAddrCast = CastInst::CreatePointerCast(data,
+ ArgStructTy->getPointerTo(),
+ "argStructCast.addr",
+ RI);
+
+ // Result struct is the last element of the packed struct passed to launch
+ unsigned outStructIdx = ArgStructTy->getNumElements() - 1;
+
+ ConstantInt *IntZero = ConstantInt::get(Type::getInt32Ty(M.getContext()), 0);
+ ConstantInt *IntIdx = ConstantInt::get(Type::getInt32Ty(M.getContext()),
+ outStructIdx);
+
+ Value* GEPIIdxList[] = { IntZero,
+ IntIdx
+ };
+ // Get data pointer to the last element of struct - result field
+ GetElementPtrInst *OutGEPI =
+ GetElementPtrInst::Create(ArgStructTy,
+ OutputAddrCast,
+ ArrayRef<Value*>(GEPIIdxList, 2),
+ CI->getName()+".addr",
+ RI);
+ // Store result there
+ new StoreInst(CI, OutGEPI, RI);
+ } else {
+ // There is no return - no need to actually code gen, but for fewer
+ // changes maintain what code was already doing
+ // We were casting the data pointer to the result type of Root, and
+ // returning result there. This would work at the LLVM level, but not
+ // at the C level, thus the rewrite.
+ CastInst* OutputAddrCast = CastInst::CreatePointerCast(data,
+ CI->getType()->getPointerTo(),
+ CI->getName()+".addr",
+ RI);
+ new StoreInst(CI, OutputAddrCast, RI);
+ }
+
switchToTimer(visc_TimerID_NONE, RI);
DEBUG(errs() << "Application specific function:\n");
--
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