lib/cfg.js - compiler-explorer - Rivoreo Source Code Repositories

 // Copyright (c) 2012-2018, Najjar Chedy
 //
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 //     * Redistributions of source code must retain the above copyright notice,
 //       this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above copyright
 //       notice, this list of conditions and the following disclaimer in the
 //       documentation and/or other materials provided with the distribution.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 const _ = require('underscore-node'),
     logger = require('./logger').logger;

 const InstructionType_jmp = 0;
 const InstructionType_conditionalJmpInst = 1;
 const InstructionType_notRetInst = 2;
 const InstructionType_retInst = 3;

 // deal with typeinfo name for, typeinfo for, vtable for
 const isFunctionName = x => x.text.trim().indexOf('.') !== 0 && !x.text.includes(' for ');

 const gccX86 = {
     filterData: asmArr => {
         const jmpLabelRegex = /\.L\d+:/;
         const isCode = x => x && x.text && (x.source !== null || jmpLabelRegex.test(x.text) || isFunctionName(x));
         return _.chain(asmArr)
             .map(_.clone)
             .filter(isCode)
             .value();
     },
     isFunctionEnd: x => x[0] !== ' ' && x[0] !== '.' && x.indexOf(':') !== -1,

     isBasicBlockEnd: (inst, prevInst) => inst[0] === '.' || prevInst.includes(' ret'),

     getInstructionType: inst => {
         if (inst.includes('jmp')) return InstructionType_jmp;
         else if (inst.trim()[0] === 'j') return InstructionType_conditionalJmpInst;
         else if (!inst.includes(' ret')) return InstructionType_notRetInst;
         else return InstructionType_retInst;
     },

     extractNodeName: inst => inst.match(/\.L\d+/) + ':',

     isJmpInstruction: x => x.trim()[0] === 'j'
 };

 const clangX86 = {
     filterData: asmArr => {
         const jmpLabelRegex = /\.LBB\d+_\d+:/;
         const isCode = x => x && x.text && (x.source !== null || jmpLabelRegex.test(x.text) || isFunctionName(x));

         const removeComments = x => {
             const pos = x.text.indexOf('#');
             if (pos !== -1)
                 x.text = x.text.substring(0, pos - 1);
             return x;
         };

         return _.chain(asmArr)
             .map(_.clone)
             .filter(isCode)
             .map(removeComments)
             .value();
     },
     isFunctionEnd: x => x[0] !== ' ' && x[0] !== '.' && x.indexOf(':') !== -1,

     isBasicBlockEnd: (inst, prevInst) => inst[0] === '.' || prevInst.includes(' ret'),

     getInstructionType: function (inst) {
         if (inst.includes('jmp')) return InstructionType_jmp;
         else if (inst.trim()[0] === 'j') return InstructionType_conditionalJmpInst;
         else if (!inst.includes(' ret')) return InstructionType_notRetInst;
         else return InstructionType_retInst;
     },

     extractNodeName: inst => inst.match(/\.LBB\d+_\d+/) + ':',

     isJmpInstruction: x => x.trim()[0] === 'j'
 };

 function splitToFunctions(asmArr, isEnd) {
     if (asmArr.length === 0) return [];
     const result = [];
     let first = 1;
     const last = asmArr.length;
     const fnRange = {start: 0, end: null};
     while (first !== last) {
         if (isEnd(asmArr[first].text)) {
             fnRange.end = first;
             result.push(_.clone(fnRange));
             fnRange.start = first;
         }
         ++first;
     }

     fnRange.end = last;
     result.push(_.clone(fnRange));
     return result;
 }

 function splitToBasicBlocks(asmArr, range, isEnd, isJmp) {
     let first = range.start;
     const last = range.end;
     if (first === last) return [];
     const functionName = asmArr[first].text;
     ++first;

     let rangeBb = {nameId: functionName.substr(0, 50), start: first, end: null, actionPos: []};
     const result = [];

     const newRangeWith = function (oldRange, nameId, start) {
         return {nameId: nameId, start: start, actionPos: [], end: oldRange.end};
     };

     while (first < last) {
         const inst = asmArr[first].text;
         if (isEnd(inst, asmArr[first - 1] ? asmArr[first - 1].text : '')) {
             rangeBb.end = first;
             result.push(_.clone(rangeBb));
             //inst is expected to be .L*: where * in 1,2,...
             rangeBb = newRangeWith(rangeBb, inst, first + 1);
         }
         else if (isJmp(inst)) {
             rangeBb.actionPos.push(first);
         }
         ++first;
     }

     rangeBb.end = last;
     result.push(_.clone(rangeBb));
     return result;
 }

 function splitToCanonicalBasicBlock(basicBlock) {
     const actionPos = basicBlock.actionPos;
     let actPosSz = actionPos.length;
     if (actionPos[actPosSz - 1] + 1 === basicBlock.end) {
         --actPosSz;
     }

     if (actPosSz === 0)
         return [{
             nameId: basicBlock.nameId,
             start: basicBlock.start,
             end: basicBlock.end
         }];
     else if (actPosSz === 1)
         return [
             {nameId: basicBlock.nameId, start: basicBlock.start, end: actionPos[0] + 1},
             {nameId: basicBlock.nameId + '@' + (actionPos[0] + 1), start: actionPos[0] + 1, end: basicBlock.end}
         ];
     else {
         let first = 0;
         const last = actPosSz;
         const blockName = basicBlock.nameId;
         let tmp = {nameId: blockName, start: basicBlock.start, end: actionPos[first] + 1};
         const result = [];
         result.push(_.clone(tmp));
         while (first !== last - 1) {
             tmp.nameId = blockName + '@' + (actionPos[first] + 1);
             tmp.start = actionPos[first] + 1;
             ++first;
             tmp.end = actionPos[first] + 1;
             result.push(_.clone(tmp));
         }

         tmp = {nameId: blockName + '@' + (actionPos[first] + 1), start: actionPos[first] + 1, end: basicBlock.end};
         result.push(_.clone(tmp));

         return result;

     }
 }

 function concatInstructions(asmArr, first, last) {
     return _.chain(asmArr.slice(first, last))
         .map(x => x.text.substr(0, 50))
         .value()
         .join('\n');
 }

 function makeNodes(asms, arrOfCanonicalBasicBlock) {
     return _.map(arrOfCanonicalBasicBlock, e => {
         return {
             id: e.nameId,
             label: `${e.nameId}${e.nameId.indexOf(':') !== -1 ? '' : ':'}\n${concatInstructions(asms, e.start, e.end)}`,
             color: '#99ccff',
             shape: 'box'
         };
     });
 }

 function makeEdges(asmArr, arrOfCanonicalBasicBlock, rules) {
     const edge = {};
     const edges = [];

     const setEdge = function (edge, sourceNode, targetNode, color) {
         edge.from = sourceNode;
         edge.to = targetNode;
         edge.arrows = 'to';
         edge.color = color;
     };
     const isBasicBlockEnd = rules.isBasicBlockEnd;

     const hasName = function (asmArr, cbb) {
         const asm = asmArr[cbb.end];
         return asm ? isBasicBlockEnd(asm.text, '') : false;
     };

     const generateName = function (name, suffix) {
         const pos = name.indexOf('@');
         if (pos === -1)
             return name + '@' + suffix;

         return name.substring(0, pos + 1) + suffix;
     };
     /* note: x.end-1 possible values:
         jmp .L*, {jne,je,jg,...} .L*, ret/rep ret, call and any other instruction that doesn't change control flow
     */

     _.each(arrOfCanonicalBasicBlock, function (x) {
         let targetNode;
         const lastInst = asmArr[x.end - 1].text;
         switch (rules.getInstructionType(lastInst)) {
             case InstructionType_jmp: {
                 //we have to deal only with jmp destination, jmp instruction are always taken.
                 //edge from jump inst
                 targetNode = rules.extractNodeName(lastInst);
                 setEdge(edge, x.nameId, targetNode, 'blue');
                 edges.push(_.clone(edge));
                 break;
             }
             case InstructionType_conditionalJmpInst: {
                 //deal with : branch taken, branch not taken
                 targetNode = rules.extractNodeName(lastInst);
                 setEdge(edge, x.nameId, targetNode, 'green');
                 edges.push(_.clone(edge));
                 targetNode = hasName(asmArr, x) ? asmArr[x.end].text : generateName(x.nameId, x.end);
                 setEdge(edge, x.nameId, targetNode, 'red');
                 edges.push(_.clone(edge));
                 logger.debug(edge);
                 break;
             }
             case InstructionType_notRetInst: {
                 //precondition: lastInst is not last instruction in asmArr (but it is in canonical basic block)
                 //note : asmArr[x.end] expected to be .L*:(name of a basic block)
                 //       this .L*: has to be exactly after the last instruction in the current canonical basic block
                 if (asmArr[x.end]) {
                     targetNode = asmArr[x.end].text;
                     setEdge(edge, x.nameId, targetNode, 'grey');
                     edges.push(_.clone(edge));
                 }
                 break;
             }
             case InstructionType_retInst:
                 break;
         }
     });
     logger.debug(edges);
     return edges;
 }


 function generateCfgStructure(version, asmArr) {
     const rules = version.includes('clang') ? clangX86 : gccX86;
     const code = rules.filterData(asmArr);
     const funcs = splitToFunctions(code, rules.isFunctionEnd);
     if (!funcs.length) {
         return funcs;
     }
     const result = {};
     _.each(funcs, _.bind(function (rng) {
         const basicBlocks = splitToBasicBlocks(code, rng, rules.isBasicBlockEnd, rules.isJmpInstruction);
         let arrOfCanonicalBasicBlock = [];
         _.each(basicBlocks, _.bind(function (elm) {
             const tmp = splitToCanonicalBasicBlock(elm);
             arrOfCanonicalBasicBlock = arrOfCanonicalBasicBlock.concat(tmp);
         }, this));

         result[code[rng.start].text] = {
             nodes: makeNodes(code, arrOfCanonicalBasicBlock),
             edges: makeEdges(code, arrOfCanonicalBasicBlock, rules)
         };
     }, this));

     return result;
 }

 module.exports.generateStructure = generateCfgStructure;
	// Copyright (c) 2012-2018, Najjar Chedy
	//
	// All rights reserved.
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// * Redistributions of source code must retain the above copyright notice,
	// this list of conditions and the following disclaimer.
	// * Redistributions in binary form must reproduce the above copyright
	// notice, this list of conditions and the following disclaimer in the
	// documentation and/or other materials provided with the distribution.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
	// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	// POSSIBILITY OF SUCH DAMAGE.
	const _ = require('underscore-node'),
	logger = require('./logger').logger;

	const InstructionType_jmp = 0;
	const InstructionType_conditionalJmpInst = 1;
	const InstructionType_notRetInst = 2;
	const InstructionType_retInst = 3;

	// deal with typeinfo name for, typeinfo for, vtable for
	const isFunctionName = x => x.text.trim().indexOf('.') !== 0 && !x.text.includes(' for ');

	const gccX86 = {
	filterData: asmArr => {
	const jmpLabelRegex = /\.L\d+:/;
	const isCode = x => x && x.text && (x.source !== null \|\| jmpLabelRegex.test(x.text) \|\| isFunctionName(x));
	return _.chain(asmArr)
	.map(_.clone)
	.filter(isCode)
	.value();
	},
	isFunctionEnd: x => x[0] !== ' ' && x[0] !== '.' && x.indexOf(':') !== -1,

	isBasicBlockEnd: (inst, prevInst) => inst[0] === '.' \|\| prevInst.includes(' ret'),

	getInstructionType: inst => {
	if (inst.includes('jmp')) return InstructionType_jmp;
	else if (inst.trim()[0] === 'j') return InstructionType_conditionalJmpInst;
	else if (!inst.includes(' ret')) return InstructionType_notRetInst;
	else return InstructionType_retInst;
	},

	extractNodeName: inst => inst.match(/\.L\d+/) + ':',

	isJmpInstruction: x => x.trim()[0] === 'j'
	};

	const clangX86 = {
	filterData: asmArr => {
	const jmpLabelRegex = /\.LBB\d+_\d+:/;
	const isCode = x => x && x.text && (x.source !== null \|\| jmpLabelRegex.test(x.text) \|\| isFunctionName(x));

	const removeComments = x => {
	const pos = x.text.indexOf('#');
	if (pos !== -1)
	x.text = x.text.substring(0, pos - 1);
	return x;
	};

	return _.chain(asmArr)
	.map(_.clone)
	.filter(isCode)
	.map(removeComments)
	.value();
	},
	isFunctionEnd: x => x[0] !== ' ' && x[0] !== '.' && x.indexOf(':') !== -1,

	isBasicBlockEnd: (inst, prevInst) => inst[0] === '.' \|\| prevInst.includes(' ret'),

	getInstructionType: function (inst) {
	if (inst.includes('jmp')) return InstructionType_jmp;
	else if (inst.trim()[0] === 'j') return InstructionType_conditionalJmpInst;
	else if (!inst.includes(' ret')) return InstructionType_notRetInst;
	else return InstructionType_retInst;
	},

	extractNodeName: inst => inst.match(/\.LBB\d+_\d+/) + ':',

	isJmpInstruction: x => x.trim()[0] === 'j'
	};

	function splitToFunctions(asmArr, isEnd) {
	if (asmArr.length === 0) return [];
	const result = [];
	let first = 1;
	const last = asmArr.length;
	const fnRange = {start: 0, end: null};
	while (first !== last) {
	if (isEnd(asmArr[first].text)) {
	fnRange.end = first;
	result.push(_.clone(fnRange));
	fnRange.start = first;
	}
	++first;
	}

	fnRange.end = last;
	result.push(_.clone(fnRange));
	return result;
	}

	function splitToBasicBlocks(asmArr, range, isEnd, isJmp) {
	let first = range.start;
	const last = range.end;
	if (first === last) return [];
	const functionName = asmArr[first].text;
	++first;

	let rangeBb = {nameId: functionName.substr(0, 50), start: first, end: null, actionPos: []};
	const result = [];

	const newRangeWith = function (oldRange, nameId, start) {
	return {nameId: nameId, start: start, actionPos: [], end: oldRange.end};
	};

	while (first < last) {
	const inst = asmArr[first].text;
	if (isEnd(inst, asmArr[first - 1] ? asmArr[first - 1].text : '')) {
	rangeBb.end = first;
	result.push(_.clone(rangeBb));
	//inst is expected to be .L: where in 1,2,...
	rangeBb = newRangeWith(rangeBb, inst, first + 1);
	}
	else if (isJmp(inst)) {
	rangeBb.actionPos.push(first);
	}
	++first;
	}

	rangeBb.end = last;
	result.push(_.clone(rangeBb));
	return result;
	}

	function splitToCanonicalBasicBlock(basicBlock) {
	const actionPos = basicBlock.actionPos;
	let actPosSz = actionPos.length;
	if (actionPos[actPosSz - 1] + 1 === basicBlock.end) {
	--actPosSz;
	}

	if (actPosSz === 0)
	return [{
	nameId: basicBlock.nameId,
	start: basicBlock.start,
	end: basicBlock.end
	}];
	else if (actPosSz === 1)
	return [
	{nameId: basicBlock.nameId, start: basicBlock.start, end: actionPos[0] + 1},
	{nameId: basicBlock.nameId + '@' + (actionPos[0] + 1), start: actionPos[0] + 1, end: basicBlock.end}
	];
	else {
	let first = 0;
	const last = actPosSz;
	const blockName = basicBlock.nameId;
	let tmp = {nameId: blockName, start: basicBlock.start, end: actionPos[first] + 1};
	const result = [];
	result.push(_.clone(tmp));
	while (first !== last - 1) {
	tmp.nameId = blockName + '@' + (actionPos[first] + 1);
	tmp.start = actionPos[first] + 1;
	++first;
	tmp.end = actionPos[first] + 1;
	result.push(_.clone(tmp));
	}

	tmp = {nameId: blockName + '@' + (actionPos[first] + 1), start: actionPos[first] + 1, end: basicBlock.end};
	result.push(_.clone(tmp));

	return result;

	}
	}

	function concatInstructions(asmArr, first, last) {
	return _.chain(asmArr.slice(first, last))
	.map(x => x.text.substr(0, 50))
	.value()
	.join('\n');
	}

	function makeNodes(asms, arrOfCanonicalBasicBlock) {
	return _.map(arrOfCanonicalBasicBlock, e => {
	return {
	id: e.nameId,
	label: `${e.nameId}${e.nameId.indexOf(':') !== -1 ? '' : ':'}\n${concatInstructions(asms, e.start, e.end)}`,
	color: '#99ccff',
	shape: 'box'
	};
	});
	}

	function makeEdges(asmArr, arrOfCanonicalBasicBlock, rules) {
	const edge = {};
	const edges = [];

	const setEdge = function (edge, sourceNode, targetNode, color) {
	edge.from = sourceNode;
	edge.to = targetNode;
	edge.arrows = 'to';
	edge.color = color;
	};
	const isBasicBlockEnd = rules.isBasicBlockEnd;

	const hasName = function (asmArr, cbb) {
	const asm = asmArr[cbb.end];
	return asm ? isBasicBlockEnd(asm.text, '') : false;
	};

	const generateName = function (name, suffix) {
	const pos = name.indexOf('@');
	if (pos === -1)
	return name + '@' + suffix;

	return name.substring(0, pos + 1) + suffix;
	};
	/* note: x.end-1 possible values:
	jmp .L, {jne,je,jg,...} .L, ret/rep ret, call and any other instruction that doesn't change control flow
	*/

	_.each(arrOfCanonicalBasicBlock, function (x) {
	let targetNode;
	const lastInst = asmArr[x.end - 1].text;
	switch (rules.getInstructionType(lastInst)) {
	case InstructionType_jmp: {
	//we have to deal only with jmp destination, jmp instruction are always taken.
	//edge from jump inst
	targetNode = rules.extractNodeName(lastInst);
	setEdge(edge, x.nameId, targetNode, 'blue');
	edges.push(_.clone(edge));
	break;
	}
	case InstructionType_conditionalJmpInst: {
	//deal with : branch taken, branch not taken
	targetNode = rules.extractNodeName(lastInst);
	setEdge(edge, x.nameId, targetNode, 'green');
	edges.push(_.clone(edge));
	targetNode = hasName(asmArr, x) ? asmArr[x.end].text : generateName(x.nameId, x.end);
	setEdge(edge, x.nameId, targetNode, 'red');
	edges.push(_.clone(edge));
	logger.debug(edge);
	break;
	}
	case InstructionType_notRetInst: {
	//precondition: lastInst is not last instruction in asmArr (but it is in canonical basic block)
	//note : asmArr[x.end] expected to be .L*:(name of a basic block)
	// this .L*: has to be exactly after the last instruction in the current canonical basic block
	if (asmArr[x.end]) {
	targetNode = asmArr[x.end].text;
	setEdge(edge, x.nameId, targetNode, 'grey');
	edges.push(_.clone(edge));
	}
	break;
	}
	case InstructionType_retInst:
	break;
	}
	});
	logger.debug(edges);
	return edges;
	}


	function generateCfgStructure(version, asmArr) {
	const rules = version.includes('clang') ? clangX86 : gccX86;
	const code = rules.filterData(asmArr);
	const funcs = splitToFunctions(code, rules.isFunctionEnd);
	if (!funcs.length) {
	return funcs;
	}
	const result = {};
	_.each(funcs, _.bind(function (rng) {
	const basicBlocks = splitToBasicBlocks(code, rng, rules.isBasicBlockEnd, rules.isJmpInstruction);
	let arrOfCanonicalBasicBlock = [];
	_.each(basicBlocks, _.bind(function (elm) {
	const tmp = splitToCanonicalBasicBlock(elm);
	arrOfCanonicalBasicBlock = arrOfCanonicalBasicBlock.concat(tmp);
	}, this));

	result[code[rng.start].text] = {
	nodes: makeNodes(code, arrOfCanonicalBasicBlock),
	edges: makeEdges(code, arrOfCanonicalBasicBlock, rules)
	};
	}, this));

	return result;
	}

	module.exports.generateStructure = generateCfgStructure;