aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChris Lattner <sabre@nondot.org>2004-11-07 00:39:26 +0000
committerChris Lattner <sabre@nondot.org>2004-11-07 00:39:26 +0000
commit00a4fe48ac7d984c960f1c63b50d75668df27284 (patch)
tree1f50832f56daefb8a8c3440c440d9977bd2cfaa3
parent64a26c7bf821842abf6407e6fcaf965b49892cf9 (diff)
This is V9 specific, move it there.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17545 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r--lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp136
1 files changed, 0 insertions, 136 deletions
diff --git a/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp b/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp
deleted file mode 100644
index 40e1be5d46..0000000000
--- a/lib/Transforms/Scalar/DecomposeMultiDimRefs.cpp
+++ /dev/null
@@ -1,136 +0,0 @@
-//===- llvm/Transforms/DecomposeMultiDimRefs.cpp - Lower array refs to 1D -===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// DecomposeMultiDimRefs - Convert multi-dimensional references consisting of
-// any combination of 2 or more array and structure indices into a sequence of
-// instructions (using getelementpr and cast) so that each instruction has at
-// most one index (except structure references, which need an extra leading
-// index of [0]).
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Transforms/Scalar.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Constants.h"
-#include "llvm/Constant.h"
-#include "llvm/Instructions.h"
-#include "llvm/BasicBlock.h"
-#include "llvm/Pass.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Support/Debug.h"
-using namespace llvm;
-
-namespace {
- Statistic<> NumAdded("lowerrefs", "# of getelementptr instructions added");
-
- struct DecomposePass : public BasicBlockPass {
- virtual bool runOnBasicBlock(BasicBlock &BB);
- };
- RegisterOpt<DecomposePass> X("lowerrefs", "Decompose multi-dimensional "
- "structure/array references");
-}
-
-// runOnBasicBlock - Entry point for array or structure references with multiple
-// indices.
-//
-bool DecomposePass::runOnBasicBlock(BasicBlock &BB) {
- bool changed = false;
- for (BasicBlock::iterator II = BB.begin(); II != BB.end(); )
- if (GetElementPtrInst *gep = dyn_cast<GetElementPtrInst>(II++)) // pre-inc
- if (gep->getNumIndices() >= 2)
- changed |= DecomposeArrayRef(gep); // always modifies II
- return changed;
-}
-
-FunctionPass *llvm::createDecomposeMultiDimRefsPass() {
- return new DecomposePass();
-}
-
-static inline bool isZeroConst (Value *V) {
- return isa<Constant> (V) && (cast<Constant>(V)->isNullValue());
-}
-
-// Function: DecomposeArrayRef()
-//
-// For any GetElementPtrInst with 2 or more array and structure indices:
-//
-// opCode CompositeType* P, [uint|ubyte] idx1, ..., [uint|ubyte] idxN
-//
-// this function generates the following sequence:
-//
-// ptr1 = getElementPtr P, idx1
-// ptr2 = getElementPtr ptr1, 0, idx2
-// ...
-// ptrN-1 = getElementPtr ptrN-2, 0, idxN-1
-// opCode ptrN-1, 0, idxN // New-MAI
-//
-// Then it replaces the original instruction with this sequence,
-// and replaces all uses of the original instruction with New-MAI.
-// If idx1 is 0, we simply omit the first getElementPtr instruction.
-//
-// On return: BBI points to the instruction after the current one
-// (whether or not *BBI was replaced).
-//
-// Return value: true if the instruction was replaced; false otherwise.
-//
-bool llvm::DecomposeArrayRef(GetElementPtrInst* GEP) {
- if (GEP->getNumIndices() < 2
- || (GEP->getNumIndices() == 2
- && isZeroConst(GEP->getOperand(1)))) {
- DEBUG (std::cerr << "DecomposeArrayRef: Skipping " << *GEP);
- return false;
- } else {
- DEBUG (std::cerr << "DecomposeArrayRef: Decomposing " << *GEP);
- }
-
- BasicBlock *BB = GEP->getParent();
- Value *LastPtr = GEP->getPointerOperand();
- Instruction *InsertPoint = GEP->getNext(); // Insert before the next insn
-
- // Process each index except the last one.
- User::const_op_iterator OI = GEP->idx_begin(), OE = GEP->idx_end();
- for (; OI+1 != OE; ++OI) {
- std::vector<Value*> Indices;
-
- // If this is the first index and is 0, skip it and move on!
- if (OI == GEP->idx_begin()) {
- if (isZeroConst (*OI))
- continue;
- }
- else // Not the first index: include initial [0] to deref the last ptr
- Indices.push_back(Constant::getNullValue(Type::LongTy));
-
- Indices.push_back(*OI);
-
- // New Instruction: nextPtr1 = GetElementPtr LastPtr, Indices
- LastPtr = new GetElementPtrInst(LastPtr, Indices, "ptr1", InsertPoint);
- ++NumAdded;
- }
-
- // Now create a new instruction to replace the original one
- //
- const PointerType *PtrTy = cast<PointerType>(LastPtr->getType());
-
- // Get the final index vector, including an initial [0] as before.
- std::vector<Value*> Indices;
- Indices.push_back(Constant::getNullValue(Type::LongTy));
- Indices.push_back(*OI);
-
- Value *NewVal = new GetElementPtrInst(LastPtr, Indices, GEP->getName(),
- InsertPoint);
-
- // Replace all uses of the old instruction with the new
- GEP->replaceAllUsesWith(NewVal);
-
- // Now remove and delete the old instruction...
- BB->getInstList().erase(GEP);
-
- return true;
-}
-