Merge pull request #132 from ethereum/functionFromPC

package.json

@@ -29,7 +29,8 @@
     "tape": "^4.6.0",
     "web3": "^0.15.3",
     "yo-yo": "^1.2.1",
-    "yo-yoify": "^3.1.0"
+    "yo-yoify": "^3.1.0",
+    "solc": "^0.4.3"
   },
   "scripts": {
     "start_node": "./runNode.sh",

src/code/codeManager.js

@@ -2,13 +2,12 @@
 var traceHelper = require('../helpers/traceHelper')
 var codeResolver = require('./codeResolver')
 var EventManager = require('../lib/eventManager')
+var SourceMappingDecoder = require('../util/sourceMappingDecoder')
 
 /*
   resolve contract code referenced by vmtrace in order to be used by asm listview.
   events:
-   - indexChanged: triggered when an item is selected
-   - codeChanged: triggered when an item (in a different context) is selected
-   - loadingCode: triggerred when loading new code
+   - changed: triggered when an item is selected
    - resolvingStep: when CodeManager resolves code/selected instruction of a new step
 */
 
@@ -19,34 +18,35 @@ function CodeManager (_traceManager) {
   this.codeResolver = codeResolver
 }
 
+/**
+ * resolve the code of the given @arg stepIndex and trigger appropriate event
+ *
+ * @param {String} stepIndex - vm trace step
+ * @param {Object} tx - transaction (given by web3)
+ */
 CodeManager.prototype.resolveStep = function (stepIndex, tx) {
   if (stepIndex < 0) return
   this.event.trigger('resolvingStep')
   var self = this
   if (stepIndex === 0) {
-    self.retrieveCodeAndTrigger(tx.to, stepIndex, tx)
+    retrieveCodeAndTrigger(self, tx.to, stepIndex, tx)
   } else {
     this.traceManager.getCurrentCalledAddressAt(stepIndex, function (error, address) {
       if (error) {
         console.log(error)
       } else {
-        self.retrieveCodeAndTrigger(address, stepIndex, tx)
+        retrieveCodeAndTrigger(self, address, stepIndex, tx)
       }
     })
   }
 }
 
-CodeManager.prototype.retrieveCodeAndTrigger = function (address, stepIndex, tx) {
-  var self = this
-  this.getCode(address, function (error, result) {
-    if (!error) {
-      self.retrieveIndexAndTrigger(address, stepIndex, result.instructions)
-    } else {
-      console.log(error)
-    }
-  })
-}
-
+/**
+ * Retrieve the code located at the given @arg address
+ *
+ * @param {String} address - address of the contract to get the code from
+ * @param {Function} cb - callback function, return the bytecode
+ */
 CodeManager.prototype.getCode = function (address, cb) {
   if (traceHelper.isContractCreation(address)) {
     var codes = codeResolver.getExecutingCodeFromCache(address)
@@ -67,27 +67,84 @@ CodeManager.prototype.getCode = function (address, cb) {
   }
 }
 
-CodeManager.prototype.retrieveIndexAndTrigger = function (address, step, code) {
+/**
+ * Retrieve the called function for the current vm step for the given @arg address
+ *
+ * @param {String} stepIndex - vm trace step
+ * @param {String} sourceMap - source map given byt the compilation result
+ * @param {Object} ast - ast given by the compilation result
+ * @return {Object} return the ast node of the function
+ */
+CodeManager.prototype.getFunctionFromStep = function (stepIndex, sourceMap, ast) {
   var self = this
-  this.getInstructionIndex(address, step, function (error, result) {
-    if (!error) {
-      self.event.trigger('changed', [code, address, result])
-    } else {
+  this.traceManager.getCurrentCalledAddressAt(stepIndex, function (error, address) {
+    if (error) {
       console.log(error)
+      return { error: 'Cannot retrieve current address for ' + stepIndex }
+    } else {
+      self.traceManager.getCurrentPC(stepIndex, function (error, pc) {
+        if (error) {
+          console.log(error)
+          return { error: 'Cannot retrieve current PC for ' + stepIndex }
+        } else {
+          return self.getFunctionFromPC(address, pc, sourceMap, ast)
+        }
+      })
     }
   })
 }
 
+/**
+ * Retrieve the instruction index of the given @arg step
+ *
+ * @param {String} address - address of the current context
+ * @param {String} step - vm trace step
+ * @param {Function} callback - instruction index
+ */
 CodeManager.prototype.getInstructionIndex = function (address, step, callback) {
-  this.traceManager.getCurrentPC(step, function (error, instIndex) {
+  this.traceManager.getCurrentPC(step, function (error, pc) {
     if (error) {
       console.log(error)
       callback('Cannot retrieve current PC for ' + step, null)
     } else {
-      var itemIndex = codeResolver.getInstructionIndex(address, instIndex)
+      var itemIndex = codeResolver.getInstructionIndex(address, pc)
       callback(null, itemIndex)
     }
   })
 }
 
+/**
+ * Retrieve the called function for the given @arg pc and @arg address
+ *
+ * @param {String} address - address of the current context (used to resolve instruction index)
+ * @param {String} pc - pc that point to the instruction index
+ * @param {String} sourceMap - source map given byt the compilation result
+ * @param {Object} ast - ast given by the compilation result
+ * @return {Object} return the ast node of the function
+ */
+CodeManager.prototype.getFunctionFromPC = function (address, pc, sourceMap, ast) {
+  var instIndex = codeResolver.getInstructionIndex(address, pc)
+  return SourceMappingDecoder.findNodeAtInstructionIndex('FunctionDefinition', instIndex, sourceMap, ast)
+}
+
+function retrieveCodeAndTrigger (codeMananger, address, stepIndex, tx) {
+  codeMananger.getCode(address, function (error, result) {
+    if (!error) {
+      retrieveIndexAndTrigger(codeMananger, address, stepIndex, result.instructions)
+    } else {
+      console.log(error)
+    }
+  })
+}
+
+function retrieveIndexAndTrigger (codeMananger, address, step, code) {
+  codeMananger.getInstructionIndex(address, step, function (error, result) {
+    if (!error) {
+      codeMananger.event.trigger('changed', [code, address, result])
+    } else {
+      console.log(error)
+    }
+  })
+}
+
 module.exports = CodeManager

src/util/sourceMappingDecoder.js

 'use strict'
 var util = require('../helpers/util')
+var AstWalker = require('./astWalker')
 
 /**
  * Decompress the source mapping given by solc-bin.js
@@ -15,36 +16,7 @@ function SourceMappingDecoder () {
  * @param {String} mapping     - compressed source mapping given by solc-bin
  * @return {Object} returns the decompressed source mapping for the given index {start, length, file, jump}
  */
-SourceMappingDecoder.prototype.atIndex = function (index, mapping) {
-  var ret = {}
-  var map = mapping.split(';')
-  if (index >= map.length) {
-    index = map.length - 1
-  }
-  for (var k = index; k >= 0; k--) {
-    var current = map[k]
-    if (!current.length) {
-      continue
-    }
-    current = current.split(':')
-    if (ret.start === undefined && current[0] && current[0].length) {
-      ret.start = parseInt(current[0])
-    }
-    if (ret.length === undefined && current[1] && current[1].length) {
-      ret.length = parseInt(current[1])
-    }
-    if (ret.file === undefined && current[2] && current[2].length) {
-      ret.file = parseInt(current[2])
-    }
-    if (ret.jump === undefined && current[3] && current[3].length) {
-      ret.jump = current[3]
-    }
-    if (ret.start !== undefined && ret.length !== undefined && ret.file !== undefined && ret.jump !== undefined) {
-      break
-    }
-  }
-  return ret
-}
+SourceMappingDecoder.prototype.atIndex = atIndex
 
 /**
  * Decode the source mapping for the given compressed mapping
@@ -103,6 +75,16 @@ SourceMappingDecoder.prototype.convertOffsetToLineColumn = function (sourceLocat
   }
 }
 
+/**
+ * Retrieve the first @arg astNodeType that include the source map at arg instIndex
+ *
+ * @param {String} astNodeType - node type that include the source map instIndex
+ * @param {String} instIndex - instruction index used to retrieve the source map
+ * @param {String} sourceMap - source map given by the compilation result
+ * @param {Object} ast - ast given by the compilation result
+ */
+SourceMappingDecoder.prototype.findNodeAtInstructionIndex = findNodeAtInstructionIndex
+
 function convertFromCharPosition (pos, lineBreakPositions) {
   var line = util.findLowerBound(pos, lineBreakPositions)
   if (lineBreakPositions[line] !== pos) {
@@ -116,4 +98,76 @@ function convertFromCharPosition (pos, lineBreakPositions) {
   }
 }
 
+function sourceLocationFromAstNode (astNode) {
+  if (astNode.src) {
+    var split = astNode.src.split(':')
+    return {
+      start: parseInt(split[0]),
+      length: parseInt(split[1]),
+      file: parseInt(split[2])
+    }
+  }
+  return null
+}
+
+function findNodeAtInstructionIndex (astNodeType, instIndex, sourceMap, ast) {
+  var sourceLocation = atIndex(instIndex, sourceMap)
+  return findNodeAtSourceLocation(astNodeType, sourceLocation, ast)
+}
+
+function findNodeAtSourceLocation (astNodeType, sourceLocation, ast) {
+  var astWalker = new AstWalker()
+  var callback = {}
+  var found = null
+  callback['*'] = function (node) {
+    var nodeLocation = sourceLocationFromAstNode(node)
+    if (!nodeLocation) {
+      return true
+    }
+    if (nodeLocation.start <= sourceLocation.start && nodeLocation.start + nodeLocation.length >= sourceLocation.start + sourceLocation.length) {
+      if (astNodeType === node.name) {
+        found = node
+        return false
+      } else {
+        return true
+      }
+    } else {
+      return false
+    }
+  }
+  astWalker.walk(ast.AST, callback)
+  return found
+}
+
+function atIndex (index, mapping) {
+  var ret = {}
+  var map = mapping.split(';')
+  if (index >= map.length) {
+    index = map.length - 1
+  }
+  for (var k = index; k >= 0; k--) {
+    var current = map[k]
+    if (!current.length) {
+      continue
+    }
+    current = current.split(':')
+    if (ret.start === undefined && current[0] && current[0].length) {
+      ret.start = parseInt(current[0])
+    }
+    if (ret.length === undefined && current[1] && current[1].length) {
+      ret.length = parseInt(current[1])
+    }
+    if (ret.file === undefined && current[2] && current[2].length) {
+      ret.file = parseInt(current[2])
+    }
+    if (ret.jump === undefined && current[3] && current[3].length) {
+      ret.jump = current[3]
+    }
+    if (ret.start !== undefined && ret.length !== undefined && ret.file !== undefined && ret.jump !== undefined) {
+      break
+    }
+  }
+  return ret
+}
+
 module.exports = SourceMappingDecoder

test/sourceMappingDecoder.js

+'use strict'
+var tape = require('tape')
+var SourceMappingDecoder = require('../src/util/sourceMappingDecoder')
+var compiler = require('solc')
+
+tape('SourceMappingDecoder', function (t) {
+  t.test('SourceMappingDecoder.findNodeAtInstructionIndex', function (st) {
+    var output = compiler.compile(contracts, 0)
+    var sourceMappingDecoder = new SourceMappingDecoder()
+    var node = sourceMappingDecoder.findNodeAtInstructionIndex('FunctionDefinition', 2, output.contracts['test'].srcmapRuntime, output.sources[''])
+    st.equal(node, null)
+    node = sourceMappingDecoder.findNodeAtInstructionIndex('FunctionDefinition', 37, output.contracts['test'].srcmapRuntime, output.sources[''])
+    st.notEqual(node, null)
+    if (node) {
+      st.equal(node.attributes.name, 'f1')
+    }
+    st.end()
+  })
+})
+
+var contracts = `contract test {
+    function f1() returns (uint) {
+        uint t = 4;
+        return t;
+    }
+    
+    function f2() {
+        
+    }
+}
+`

test/tests.js

@@ -6,3 +6,4 @@ require('./util.js')
 require('./astwalker.js')
 require('./disassembler.js')
 require('./eventManager.js')
+require('./sourceMappingDecoder.js')