From: Eli Bendersky <eliben@google.com>
Date: Thu, 16 Jul 2015 20:42:38 +0000 (+0000)
Subject: Streamline the coding style in NVPTXLowerAggrCopies
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ccd3aa85a9b3f5e0701259407cf467f51b3dccd3;p=oota-llvm.git

Streamline the coding style in NVPTXLowerAggrCopies

Make the style consistent with LLVM style throughout and clang-format.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242439 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/NVPTX/NVPTXLowerAggrCopies.cpp b/lib/Target/NVPTX/NVPTXLowerAggrCopies.cpp
index 54be21d4083..91c872d709c 100644
--- a/lib/Target/NVPTX/NVPTXLowerAggrCopies.cpp
+++ b/lib/Target/NVPTX/NVPTXLowerAggrCopies.cpp
@@ -7,6 +7,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
+// \file
 // Lower aggregate copies, memset, memcpy, memmov intrinsics into loops when
 // the size is large or is not a compile-time constant.
 //
@@ -19,7 +20,6 @@
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
-#include "llvm/IR/InstIterator.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Intrinsics.h"
@@ -57,47 +57,52 @@ struct NVPTXLowerAggrCopies : public FunctionPass {
 char NVPTXLowerAggrCopies::ID = 0;
 
 // Lower memcpy to loop.
-void convertMemCpyToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
-                         Value *len, bool srcVolatile, bool dstVolatile,
-                         LLVMContext &Context, Function &F) {
-  Type *indType = len->getType();
+void convertMemCpyToLoop(Instruction *ConvertedInst, Value *SrcAddr,
+                         Value *DstAddr, Value *CopyLen, bool SrcIsVolatile,
+                         bool DstIsVolatile, LLVMContext &Context,
+                         Function &F) {
+  Type *TypeOfCopyLen = CopyLen->getType();
 
-  BasicBlock *origBB = splitAt->getParent();
-  BasicBlock *newBB = splitAt->getParent()->splitBasicBlock(splitAt, "split");
-  BasicBlock *loopBB = BasicBlock::Create(Context, "loadstoreloop", &F, newBB);
+  BasicBlock *OrigBB = ConvertedInst->getParent();
+  BasicBlock *NewBB =
+      ConvertedInst->getParent()->splitBasicBlock(ConvertedInst, "split");
+  BasicBlock *LoopBB = BasicBlock::Create(Context, "loadstoreloop", &F, NewBB);
 
-  origBB->getTerminator()->setSuccessor(0, loopBB);
-  IRBuilder<> builder(origBB, origBB->getTerminator());
+  OrigBB->getTerminator()->setSuccessor(0, LoopBB);
+  IRBuilder<> Builder(OrigBB, OrigBB->getTerminator());
 
-  // srcAddr and dstAddr are expected to be pointer types,
+  // SrcAddr and DstAddr are expected to be pointer types,
   // so no check is made here.
-  unsigned srcAS = cast<PointerType>(srcAddr->getType())->getAddressSpace();
-  unsigned dstAS = cast<PointerType>(dstAddr->getType())->getAddressSpace();
+  unsigned SrcAS = cast<PointerType>(SrcAddr->getType())->getAddressSpace();
+  unsigned DstAS = cast<PointerType>(DstAddr->getType())->getAddressSpace();
 
   // Cast pointers to (char *)
-  srcAddr = builder.CreateBitCast(srcAddr, Type::getInt8PtrTy(Context, srcAS));
-  dstAddr = builder.CreateBitCast(dstAddr, Type::getInt8PtrTy(Context, dstAS));
+  SrcAddr = Builder.CreateBitCast(SrcAddr, Builder.getInt8PtrTy(SrcAS));
+  DstAddr = Builder.CreateBitCast(DstAddr, Builder.getInt8PtrTy(DstAS));
 
-  IRBuilder<> loop(loopBB);
-  // The loop index (ind) is a phi node.
-  PHINode *ind = loop.CreatePHI(indType, 0);
-  // Incoming value for ind is 0
-  ind->addIncoming(ConstantInt::get(indType, 0), origBB);
+  IRBuilder<> LoopBuilder(LoopBB);
+  PHINode *LoopIndex = LoopBuilder.CreatePHI(TypeOfCopyLen, 0);
+  LoopIndex->addIncoming(ConstantInt::get(TypeOfCopyLen, 0), OrigBB);
 
-  // load from srcAddr+ind
+  // load from SrcAddr+LoopIndex
   // TODO: we can leverage the align parameter of llvm.memcpy for more efficient
   // word-sized loads and stores.
-  Value *val = loop.CreateLoad(loop.CreateGEP(loop.getInt8Ty(), srcAddr, ind),
-                               srcVolatile);
-  // store at dstAddr+ind
-  loop.CreateStore(val, loop.CreateGEP(loop.getInt8Ty(), dstAddr, ind),
-                   dstVolatile);
-
-  // The value for ind coming from backedge is (ind + 1)
-  Value *newind = loop.CreateAdd(ind, ConstantInt::get(indType, 1));
-  ind->addIncoming(newind, loopBB);
-
-  loop.CreateCondBr(loop.CreateICmpULT(newind, len), loopBB, newBB);
+  Value *Element = LoopBuilder.CreateLoad(
+      LoopBuilder.CreateGEP(LoopBuilder.getInt8Ty(), SrcAddr, LoopIndex),
+      SrcIsVolatile);
+  // store at DstAddr+LoopIndex
+  LoopBuilder.CreateStore(
+      Element,
+      LoopBuilder.CreateGEP(LoopBuilder.getInt8Ty(), DstAddr, LoopIndex),
+      DstIsVolatile);
+
+  // The value for LoopIndex coming from backedge is (LoopIndex + 1)
+  Value *NewIndex =
+      LoopBuilder.CreateAdd(LoopIndex, ConstantInt::get(TypeOfCopyLen, 1));
+  LoopIndex->addIncoming(NewIndex, LoopBB);
+
+  LoopBuilder.CreateCondBr(LoopBuilder.CreateICmpULT(NewIndex, CopyLen), LoopBB,
+                           NewBB);
 }
 
 // Lower memmove to IR. memmove is required to correctly copy overlapping memory
@@ -122,11 +127,12 @@ void convertMemCpyToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
 //   }
 //   return dst;
 // }
-void convertMemMoveToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
-                          Value *len, bool srcVolatile, bool dstVolatile,
-                          LLVMContext &Context, Function &F) {
-  Type *TypeOfLen = len->getType();
-  BasicBlock *OrigBB = splitAt->getParent();
+void convertMemMoveToLoop(Instruction *ConvertedInst, Value *SrcAddr,
+                          Value *DstAddr, Value *CopyLen, bool SrcIsVolatile,
+                          bool DstIsVolatile, LLVMContext &Context,
+                          Function &F) {
+  Type *TypeOfCopyLen = CopyLen->getType();
+  BasicBlock *OrigBB = ConvertedInst->getParent();
 
   // Create the a comparison of src and dst, based on which we jump to either
   // the forward-copy part of the function (if src >= dst) or the backwards-copy
@@ -134,10 +140,11 @@ void convertMemMoveToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
   // SplitBlockAndInsertIfThenElse conveniently creates the basic if-then-else
   // structure. Its block terminators (unconditional branches) are replaced by
   // the appropriate conditional branches when the loop is built.
-  ICmpInst *PtrCompare = new ICmpInst(splitAt, ICmpInst::ICMP_ULT, srcAddr,
-                                      dstAddr, "compare_src_dst");
+  ICmpInst *PtrCompare = new ICmpInst(ConvertedInst, ICmpInst::ICMP_ULT,
+                                      SrcAddr, DstAddr, "compare_src_dst");
   TerminatorInst *ThenTerm, *ElseTerm;
-  SplitBlockAndInsertIfThenElse(PtrCompare, splitAt, &ThenTerm, &ElseTerm);
+  SplitBlockAndInsertIfThenElse(PtrCompare, ConvertedInst, &ThenTerm,
+                                &ElseTerm);
 
   // Each part of the function consists of two blocks:
   //   copy_backwards:        used to skip the loop when n == 0
@@ -148,31 +155,31 @@ void convertMemMoveToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
   CopyBackwardsBB->setName("copy_backwards");
   BasicBlock *CopyForwardBB = ElseTerm->getParent();
   CopyForwardBB->setName("copy_forward");
-  BasicBlock *ExitBB = splitAt->getParent();
+  BasicBlock *ExitBB = ConvertedInst->getParent();
   ExitBB->setName("memmove_done");
 
   // Initial comparison of n == 0 that lets us skip the loops altogether. Shared
   // between both backwards and forward copy clauses.
   ICmpInst *CompareN =
-      new ICmpInst(OrigBB->getTerminator(), ICmpInst::ICMP_EQ, len,
-                   ConstantInt::get(TypeOfLen, 0), "compare_n_to_0");
+      new ICmpInst(OrigBB->getTerminator(), ICmpInst::ICMP_EQ, CopyLen,
+                   ConstantInt::get(TypeOfCopyLen, 0), "compare_n_to_0");
 
   // Copying backwards.
   BasicBlock *LoopBB =
       BasicBlock::Create(Context, "copy_backwards_loop", &F, CopyForwardBB);
   IRBuilder<> LoopBuilder(LoopBB);
-  PHINode *LoopPhi = LoopBuilder.CreatePHI(TypeOfLen, 0);
+  PHINode *LoopPhi = LoopBuilder.CreatePHI(TypeOfCopyLen, 0);
   Value *IndexPtr = LoopBuilder.CreateSub(
-      LoopPhi, ConstantInt::get(TypeOfLen, 1), "index_ptr");
+      LoopPhi, ConstantInt::get(TypeOfCopyLen, 1), "index_ptr");
   Value *Element = LoopBuilder.CreateLoad(
-      LoopBuilder.CreateInBoundsGEP(srcAddr, IndexPtr), "element");
+      LoopBuilder.CreateInBoundsGEP(SrcAddr, IndexPtr), "element");
   LoopBuilder.CreateStore(Element,
-                          LoopBuilder.CreateInBoundsGEP(dstAddr, IndexPtr));
+                          LoopBuilder.CreateInBoundsGEP(DstAddr, IndexPtr));
   LoopBuilder.CreateCondBr(
-      LoopBuilder.CreateICmpEQ(IndexPtr, ConstantInt::get(TypeOfLen, 0)),
+      LoopBuilder.CreateICmpEQ(IndexPtr, ConstantInt::get(TypeOfCopyLen, 0)),
       ExitBB, LoopBB);
   LoopPhi->addIncoming(IndexPtr, LoopBB);
-  LoopPhi->addIncoming(len, CopyBackwardsBB);
+  LoopPhi->addIncoming(CopyLen, CopyBackwardsBB);
   BranchInst::Create(ExitBB, LoopBB, CompareN, ThenTerm);
   ThenTerm->eraseFromParent();
 
@@ -180,52 +187,57 @@ void convertMemMoveToLoop(Instruction *splitAt, Value *srcAddr, Value *dstAddr,
   BasicBlock *FwdLoopBB =
       BasicBlock::Create(Context, "copy_forward_loop", &F, ExitBB);
   IRBuilder<> FwdLoopBuilder(FwdLoopBB);
-  PHINode *FwdCopyPhi = FwdLoopBuilder.CreatePHI(TypeOfLen, 0, "index_ptr");
+  PHINode *FwdCopyPhi = FwdLoopBuilder.CreatePHI(TypeOfCopyLen, 0, "index_ptr");
   Value *FwdElement = FwdLoopBuilder.CreateLoad(
-      FwdLoopBuilder.CreateInBoundsGEP(srcAddr, FwdCopyPhi), "element");
+      FwdLoopBuilder.CreateInBoundsGEP(SrcAddr, FwdCopyPhi), "element");
   FwdLoopBuilder.CreateStore(
-      FwdElement, FwdLoopBuilder.CreateInBoundsGEP(dstAddr, FwdCopyPhi));
+      FwdElement, FwdLoopBuilder.CreateInBoundsGEP(DstAddr, FwdCopyPhi));
   Value *FwdIndexPtr = FwdLoopBuilder.CreateAdd(
-      FwdCopyPhi, ConstantInt::get(TypeOfLen, 1), "index_increment");
-  FwdLoopBuilder.CreateCondBr(FwdLoopBuilder.CreateICmpEQ(FwdIndexPtr, len),
+      FwdCopyPhi, ConstantInt::get(TypeOfCopyLen, 1), "index_increment");
+  FwdLoopBuilder.CreateCondBr(FwdLoopBuilder.CreateICmpEQ(FwdIndexPtr, CopyLen),
                               ExitBB, FwdLoopBB);
   FwdCopyPhi->addIncoming(FwdIndexPtr, FwdLoopBB);
-  FwdCopyPhi->addIncoming(ConstantInt::get(TypeOfLen, 0), CopyForwardBB);
+  FwdCopyPhi->addIncoming(ConstantInt::get(TypeOfCopyLen, 0), CopyForwardBB);
 
   BranchInst::Create(ExitBB, FwdLoopBB, CompareN, ElseTerm);
   ElseTerm->eraseFromParent();
 }
 
 // Lower memset to loop.
-void convertMemSetToLoop(Instruction *splitAt, Value *dstAddr, Value *len,
-                         Value *val, LLVMContext &Context, Function &F) {
-  BasicBlock *origBB = splitAt->getParent();
-  BasicBlock *newBB = splitAt->getParent()->splitBasicBlock(splitAt, "split");
-  BasicBlock *loopBB = BasicBlock::Create(Context, "loadstoreloop", &F, newBB);
+void convertMemSetToLoop(Instruction *ConvertedInst, Value *DstAddr,
+                         Value *CopyLen, Value *SetValue, LLVMContext &Context,
+                         Function &F) {
+  BasicBlock *OrigBB = ConvertedInst->getParent();
+  BasicBlock *NewBB =
+      ConvertedInst->getParent()->splitBasicBlock(ConvertedInst, "split");
+  BasicBlock *LoopBB = BasicBlock::Create(Context, "loadstoreloop", &F, NewBB);
 
-  origBB->getTerminator()->setSuccessor(0, loopBB);
-  IRBuilder<> builder(origBB, origBB->getTerminator());
-
-  unsigned dstAS = cast<PointerType>(dstAddr->getType())->getAddressSpace();
+  OrigBB->getTerminator()->setSuccessor(0, LoopBB);
+  IRBuilder<> Builder(OrigBB, OrigBB->getTerminator());
 
   // Cast pointer to the type of value getting stored
-  dstAddr =
-      builder.CreateBitCast(dstAddr, PointerType::get(val->getType(), dstAS));
+  unsigned dstAS = cast<PointerType>(DstAddr->getType())->getAddressSpace();
+  DstAddr = Builder.CreateBitCast(DstAddr,
+                                  PointerType::get(SetValue->getType(), dstAS));
 
-  IRBuilder<> loop(loopBB);
-  PHINode *ind = loop.CreatePHI(len->getType(), 0);
-  ind->addIncoming(ConstantInt::get(len->getType(), 0), origBB);
+  IRBuilder<> LoopBuilder(LoopBB);
+  PHINode *LoopIndex = LoopBuilder.CreatePHI(CopyLen->getType(), 0);
+  LoopIndex->addIncoming(ConstantInt::get(CopyLen->getType(), 0), OrigBB);
 
-  loop.CreateStore(val, loop.CreateGEP(val->getType(), dstAddr, ind), false);
+  LoopBuilder.CreateStore(
+      SetValue, LoopBuilder.CreateGEP(SetValue->getType(), DstAddr, LoopIndex),
+      false);
 
-  Value *newind = loop.CreateAdd(ind, ConstantInt::get(len->getType(), 1));
-  ind->addIncoming(newind, loopBB);
+  Value *NewIndex =
+      LoopBuilder.CreateAdd(LoopIndex, ConstantInt::get(CopyLen->getType(), 1));
+  LoopIndex->addIncoming(NewIndex, LoopBB);
 
-  loop.CreateCondBr(loop.CreateICmpULT(newind, len), loopBB, newBB);
+  LoopBuilder.CreateCondBr(LoopBuilder.CreateICmpULT(NewIndex, CopyLen), LoopBB,
+                           NewBB);
 }
 
 bool NVPTXLowerAggrCopies::runOnFunction(Function &F) {
-  SmallVector<LoadInst *, 4> aggrLoads;
+  SmallVector<LoadInst *, 4> AggrLoads;
   SmallVector<MemIntrinsic *, 4> MemCalls;
 
   const DataLayout &DL = F.getParent()->getDataLayout();
@@ -235,18 +247,17 @@ bool NVPTXLowerAggrCopies::runOnFunction(Function &F) {
   for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; ++BI) {
     for (BasicBlock::iterator II = BI->begin(), IE = BI->end(); II != IE;
          ++II) {
-      if (LoadInst *load = dyn_cast<LoadInst>(II)) {
-        if (!load->hasOneUse())
+      if (LoadInst *LI = dyn_cast<LoadInst>(II)) {
+        if (!LI->hasOneUse())
           continue;
 
-        if (DL.getTypeStoreSize(load->getType()) < MaxAggrCopySize)
+        if (DL.getTypeStoreSize(LI->getType()) < MaxAggrCopySize)
           continue;
 
-        User *use = load->user_back();
-        if (StoreInst *store = dyn_cast<StoreInst>(use)) {
-          if (store->getOperand(0) != load)
+        if (StoreInst *SI = dyn_cast<StoreInst>(LI->user_back())) {
+          if (SI->getOperand(0) != LI)
             continue;
-          aggrLoads.push_back(load);
+          AggrLoads.push_back(LI);
         }
       } else if (MemIntrinsic *IntrCall = dyn_cast<MemIntrinsic>(II)) {
         // Convert intrinsic calls with variable size or with constant size
@@ -262,55 +273,60 @@ bool NVPTXLowerAggrCopies::runOnFunction(Function &F) {
     }
   }
 
-  if (aggrLoads.size() == 0 && MemCalls.size() == 0) {
+  if (AggrLoads.size() == 0 && MemCalls.size() == 0) {
     return false;
   }
 
   //
   // Do the transformation of an aggr load/copy/set to a loop
   //
-  for (LoadInst *load : aggrLoads) {
-    StoreInst *store = dyn_cast<StoreInst>(*load->user_begin());
-    Value *srcAddr = load->getOperand(0);
-    Value *dstAddr = store->getOperand(1);
-    unsigned numLoads = DL.getTypeStoreSize(load->getType());
-    Value *len = ConstantInt::get(Type::getInt32Ty(Context), numLoads);
-
-    convertMemCpyToLoop(store, srcAddr, dstAddr, len, load->isVolatile(),
-                        store->isVolatile(), Context, F);
-
-    store->eraseFromParent();
-    load->eraseFromParent();
+  for (LoadInst *LI : AggrLoads) {
+    StoreInst *SI = dyn_cast<StoreInst>(*LI->user_begin());
+    Value *SrcAddr = LI->getOperand(0);
+    Value *DstAddr = SI->getOperand(1);
+    unsigned NumLoads = DL.getTypeStoreSize(LI->getType());
+    Value *CopyLen = ConstantInt::get(Type::getInt32Ty(Context), NumLoads);
+
+    convertMemCpyToLoop(/* ConvertedInst */ SI,
+                        /* SrcAddr */ SrcAddr, /* DstAddr */ DstAddr,
+                        /* CopyLen */ CopyLen,
+                        /* SrcIsVolatile */ LI->isVolatile(),
+                        /* DstIsVolatile */ SI->isVolatile(),
+                        /* Context */ Context,
+                        /* Function F */ F);
+
+    SI->eraseFromParent();
+    LI->eraseFromParent();
   }
 
   // Transform mem* intrinsic calls.
   for (MemIntrinsic *MemCall : MemCalls) {
     if (MemCpyInst *Memcpy = dyn_cast<MemCpyInst>(MemCall)) {
-      convertMemCpyToLoop(/* splitAt */ Memcpy,
-                          /* srcAddr */ Memcpy->getRawSource(),
-                          /* dstAddr */ Memcpy->getRawDest(),
-                          /* len */ Memcpy->getLength(),
-                          /* srcVolatile */ Memcpy->isVolatile(),
-                          /* dstVolatile */ Memcpy->isVolatile(),
+      convertMemCpyToLoop(/* ConvertedInst */ Memcpy,
+                          /* SrcAddr */ Memcpy->getRawSource(),
+                          /* DstAddr */ Memcpy->getRawDest(),
+                          /* CopyLen */ Memcpy->getLength(),
+                          /* SrcIsVolatile */ Memcpy->isVolatile(),
+                          /* DstIsVolatile */ Memcpy->isVolatile(),
                           /* Context */ Context,
                           /* Function F */ F);
     } else if (MemMoveInst *Memmove = dyn_cast<MemMoveInst>(MemCall)) {
-      convertMemMoveToLoop(/* splitAt */ Memmove,
-                           /* srcAddr */ Memmove->getRawSource(),
-                           /* dstAddr */ Memmove->getRawDest(),
-                           /* len */ Memmove->getLength(),
-                           /* srcVolatile */ Memmove->isVolatile(),
-                           /* dstVolatile */ Memmove->isVolatile(),
+      convertMemMoveToLoop(/* ConvertedInst */ Memmove,
+                           /* SrcAddr */ Memmove->getRawSource(),
+                           /* DstAddr */ Memmove->getRawDest(),
+                           /* CopyLen */ Memmove->getLength(),
+                           /* SrcIsVolatile */ Memmove->isVolatile(),
+                           /* DstIsVolatile */ Memmove->isVolatile(),
                            /* Context */ Context,
                            /* Function F */ F);
 
     } else if (MemSetInst *Memset = dyn_cast<MemSetInst>(MemCall)) {
-      convertMemSetToLoop(/* splitAt */ Memset,
-                          /* dstAddr */ Memset->getRawDest(),
-                          /* len */ Memset->getLength(),
-                          /* val */ Memset->getValue(),
+      convertMemSetToLoop(/* ConvertedInst */ Memset,
+                          /* DstAddr */ Memset->getRawDest(),
+                          /* CopyLen */ Memset->getLength(),
+                          /* SetValue */ Memset->getValue(),
                           /* Context */ Context,
-                          /* F */ F);
+                          /* Function F */ F);
     }
     MemCall->eraseFromParent();
   }