verilator/src/V3DepthBlock.cpp

143 lines
4.2 KiB
C++
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// -*- mode: C++; c-file-style: "cc-mode" -*-
//*************************************************************************
// DESCRIPTION: Verilator: Prevent very deep expressions
//
// Code available from: http://www.veripool.org/verilator
//
//*************************************************************************
//
// Copyright 2003-2018 by Wilson Snyder. This program is free software; you can
// redistribute it and/or modify it under the terms of either the GNU
// Lesser General Public License Version 3 or the Perl Artistic License
// Version 2.0.
//
// Verilator is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
//*************************************************************************
// V3DepthBlock's Transformations:
//
// Each module:
// For each deep block, create cfunc including that block.
//
//*************************************************************************
#include "config_build.h"
#include "verilatedos.h"
#include <cstdio>
#include <cstdarg>
#include <unistd.h>
#include <algorithm>
#include "V3Global.h"
#include "V3DepthBlock.h"
#include "V3Ast.h"
#include "V3EmitCBase.h"
//######################################################################
class DepthBlockVisitor : public AstNVisitor {
private:
// NODE STATE
// STATE
AstNodeModule* m_modp; // Current module
AstCFunc* m_funcp; // Current function
int m_depth; // How deep in an expression
int m_deepNum; // How many functions made
// METHODS
VL_DEBUG_FUNC; // Declare debug()
AstCFunc* createDeepFunc(AstNode* nodep) {
AstNRelinker relinkHandle;
nodep->unlinkFrBack(&relinkHandle);
// Create function
string name = m_funcp->name()+"__deep"+cvtToStr(++m_deepNum);
AstCFunc* funcp = new AstCFunc(nodep->fileline(), name, NULL);
funcp->argTypes(EmitCBaseVisitor::symClassVar());
funcp->symProlog(true);
funcp->slow(m_funcp->slow());
funcp->addStmtsp(nodep);
m_modp->addStmtp(funcp);
// Call it at the point where the body was removed from
AstCCall* callp = new AstCCall(nodep->fileline(), funcp);
callp->argTypes("vlSymsp");
UINFO(6," New "<<callp<<endl);
//
relinkHandle.relink(callp);
return funcp;
}
// VISITORS
virtual void visit(AstNodeModule* nodep) {
UINFO(4," MOD "<<nodep<<endl);
m_modp = nodep;
m_deepNum = 0;
iterateChildren(nodep);
m_modp = NULL;
}
virtual void visit(AstCFunc* nodep) {
// We recurse into this.
int lastDepth = m_depth;
AstCFunc* lastFuncp = m_funcp;
{
m_depth = 0;
m_funcp = nodep;
iterateChildren(nodep);
}
m_depth = lastDepth;
m_funcp = lastFuncp;
}
void visitStmt(AstNodeStmt* nodep) {
m_depth++;
if (m_depth > v3Global.opt.compLimitBlocks()
&& !VN_IS(nodep, CCall)) { // Already done
UINFO(4, "DeepBlocks "<<m_depth<<" "<<nodep<<endl);
AstNode* backp = nodep->backp(); // Only for debug
if (debug()>=9) backp->dumpTree(cout,"- pre : ");
AstCFunc* funcp = createDeepFunc(nodep);
iterate(funcp);
if (debug()>=9) backp->dumpTree(cout,"- post: ");
if (debug()>=9) funcp->dumpTree(cout,"- func: ");
} else {
iterateChildren(nodep);
}
m_depth--;
}
virtual void visit(AstNodeStmt* nodep) {
visitStmt(nodep);
}
virtual void visit(AstNodeMath* nodep) {} // Accelerate
//--------------------
// Default: Just iterate
virtual void visit(AstVar* nodep) {} // Don't hit varrefs under vars
virtual void visit(AstNode* nodep) {
iterateChildren(nodep);
}
public:
// CONSTUCTORS
explicit DepthBlockVisitor(AstNetlist* nodep) {
m_modp=NULL;
m_depth=0;
//
iterate(nodep);
}
virtual ~DepthBlockVisitor() {}
};
//######################################################################
// DepthBlock class functions
void V3DepthBlock::depthBlockAll(AstNetlist* nodep) {
UINFO(2,__FUNCTION__<<": "<<endl);
{
DepthBlockVisitor visitor (nodep);
} // Destruct before checking
V3Global::dumpCheckGlobalTree("deepblock", 0, v3Global.opt.dumpTreeLevel(__FILE__) >= 3);
}