1 //===-- AllocaHoisting.cpp - Hoist allocas to the entry block --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Hoist the alloca instructions in the non-entry blocks to the entry blocks.
12 //===----------------------------------------------------------------------===//
14 #include "NVPTXAllocaHoisting.h"
15 #include "llvm/IR/Constants.h"
16 #include "llvm/IR/Function.h"
17 #include "llvm/IR/Instructions.h"
21 bool NVPTXAllocaHoisting::runOnFunction(Function &function) {
22 bool functionModified = false;
23 Function::iterator I = function.begin();
24 TerminatorInst *firstTerminatorInst = (I++)->getTerminator();
26 for (Function::iterator E = function.end(); I != E; ++I) {
27 for (BasicBlock::iterator BI = I->begin(), BE = I->end(); BI != BE;) {
28 AllocaInst *allocaInst = dyn_cast<AllocaInst>(BI++);
29 if (allocaInst && isa<ConstantInt>(allocaInst->getArraySize())) {
30 allocaInst->moveBefore(firstTerminatorInst);
31 functionModified = true;
36 return functionModified;
39 char NVPTXAllocaHoisting::ID = 1;
40 RegisterPass<NVPTXAllocaHoisting> X("alloca-hoisting",
41 "Hoisting alloca instructions in non-entry "
42 "blocks to the entry block");
44 FunctionPass *createAllocaHoisting() {
45 return new NVPTXAllocaHoisting();
48 } // end namespace llvm