This pass is now obsolete since all targets have moved to the SelectionDAG

infrastructure and the simple isels have been removed.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24090 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Scalar/LowerConstantExprs.cpp b/lib/Transforms/Scalar/LowerConstantExprs.cpp
deleted file mode 100644 (file)
index cccf9e0..0000000
--- a/lib/Transforms/Scalar/LowerConstantExprs.cpp
+++ /dev/null
@@ -1,170 +0,0 @@
-//===-- lib/Transforms/Scalar/LowerConstantExprs.cpp ------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file was written by Vladimir Prus and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines the LowerConstantExpression pass, which converts all
-// constant expressions into instructions. This is primarily usefull for
-// code generators which don't yet want or don't have a need to handle
-// constant expressions themself.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Pass.h"
-#include "llvm/Function.h"
-#include "llvm/Constants.h"
-#include "llvm/Instructions.h"
-#include "llvm/Support/InstIterator.h"
-#include <vector>
-#include <iostream>
-
-using namespace llvm;
-using namespace std;
-
-namespace {
-
-    class ConstantExpressionsLower : public FunctionPass {
-    private: // FunctionPass overrides
-
-        bool runOnFunction(Function& f);
-
-    private: // internal methods
-
-        /// For all operands of 'insn' which are constant expressions, generates
-        /// an appropriate instruction and replaces the use of constant
-        /// expression with the use of the generated instruction.
-        bool runOnInstruction(Instruction& insn);
-
-        /// Given an constant expression 'c' which occures in 'instruction',
-        /// at position 'pos',
-        /// generates instruction to compute 'c' and replaces the use of 'c'
-        /// with the use of that instruction. This handles only top-level
-        /// expression in 'c', any subexpressions are not handled.
-        Instruction* convert(const ConstantExpr& c, Instruction* where);
-    };
-
-    RegisterOpt<ConstantExpressionsLower> X(
-        "lowerconstantexprs", "Lower constant expressions");
-}
-
-bool ConstantExpressionsLower::runOnFunction(Function& f)
-{
-    bool modified = false;
-    for (inst_iterator i = inst_begin(f), e = inst_end(f); i != e; ++i)
-    {
-        modified |= runOnInstruction(*i);
-    }
-    return modified;
-}
-
-bool ConstantExpressionsLower::runOnInstruction(Instruction& instruction)
-{
-    bool modified = false;
-    for (unsigned pos = 0; pos < instruction.getNumOperands(); ++pos)
-    {
-        if (ConstantExpr* ce
-            = dyn_cast<ConstantExpr>(instruction.getOperand(pos))) {
-
-            // Decide where to insert the new instruction
-            Instruction* where = &instruction;
-
-            // For PHI nodes we can't insert new instruction before phi,
-            // since phi should always come at the beginning of the
-            // basic block.
-            // So, we need to insert it in the predecessor, right before
-            // the terminating instruction.
-            if (PHINode* p = dyn_cast<PHINode>(&instruction)) {
-                BasicBlock* predecessor = 0;
-                for(unsigned i = 0; i < p->getNumIncomingValues(); ++i)
-                    if (p->getIncomingValue(i) == ce) {
-                        predecessor = p->getIncomingBlock(i);
-                        break;
-                    }
-                assert(predecessor && "could not find predecessor");
-                where = predecessor->getTerminator();
-            }
-            Instruction* n = convert(*ce, where);
-
-            // Note: we can't call replaceAllUsesWith, since
-            // that might replace uses in another functions,
-            // where the instruction(s) we've generated are not
-            // available.
-
-            // Moreover, we can't replace all the users in the same
-            // function, because we can't be sure the definition
-            // made in this block will be available in other
-            // places where the constant is used.
-            instruction.setOperand(pos, n);
-
-            // The new instruction might have constant expressions in
-            // it. Extract them too.
-            runOnInstruction(*n);
-            modified = true;
-        }
-    }
-    return modified;
-}
-
-Instruction*
-ConstantExpressionsLower::convert(const ConstantExpr& c, Instruction* where)
-{
-    Instruction* result = 0;
-
-    if (c.getOpcode() >= Instruction::BinaryOpsBegin &&
-        c.getOpcode() < Instruction::BinaryOpsEnd)
-    {
-        result = BinaryOperator::create(
-            static_cast<Instruction::BinaryOps>(c.getOpcode()),
-            c.getOperand(0), c.getOperand(1), "", where);
-    }
-    else
-    {
-        switch(c.getOpcode()) {
-        case Instruction::GetElementPtr:
-        {
-            vector<Value*> idx;
-            for (unsigned i = 1; i < c.getNumOperands(); ++i)
-                idx.push_back(c.getOperand(i));
-            result = new GetElementPtrInst(c.getOperand(0),
-                                           idx, "", where);
-            break;
-        }
-
-        case Instruction::Cast:
-            result = new CastInst(c.getOperand(0), c.getType(), "",
-                                  where);
-            break;
-
-
-        case Instruction::Shl:
-        case Instruction::Shr:
-            result = new ShiftInst(
-                static_cast<Instruction::OtherOps>(c.getOpcode()),
-                c.getOperand(0), c.getOperand(1), "", where);
-            break;
-
-        case Instruction::Select:
-            result = new SelectInst(c.getOperand(0), c.getOperand(1),
-                                    c.getOperand(2), "", where);
-            break;
-
-        default:
-            std::cerr << "Offending expr: " << c << "\n";
-            assert(0 && "Constant expression not yet handled!\n");
-        }
-    }
-    return result;
-}
-
-
-
-namespace llvm {
-    FunctionPass* createLowerConstantExpressionsPass()
-    {
-        return new ConstantExpressionsLower;
-    }
-}