Changeset 35245 in webkit for trunk/JavaScriptCore/VM/CodeGenerator.h

Timestamp:

Jul 18, 2008, 6:44:24 PM (17 years ago)

Author:

[email protected]

Message:

Bug 18774: SQUIRRELFISH: print meaningful error messages <​https://bugs.webkit.org/show_bug.cgi?id=18774>
<rdar://problem/5769353> SQUIRRELFISH: JavaScript error messages are missing informative text

Reviewed by Cameron Zwarich

Add support for decent error messages in JavaScript. This patch achieves this by providing
ensuring the common errors and exceptions have messages that provide the text of expression
that trigger the exception. In addition it attaches a number of properties to the exception
object detailing where in the source the expression came from.

File:

• trunk/JavaScriptCore/VM/CodeGenerator.h (modified) (3 diffs)

trunk/JavaScriptCore/VM/CodeGenerator.h

@@ -183 +183 @@
         }
 
+        void emitExpressionInfo(unsigned divot, unsigned startOffset, unsigned endOffset)
+        { 
+            divot -= m_codeBlock->sourceOffset;
+            if (divot > ExpressionRangeInfo::MaxDivot) {
+                // Overflow has occurred, we can only give line number info for errors for this region
+                divot = 0;
+                startOffset = 0;
+                endOffset = 0;
+            } else if (startOffset > ExpressionRangeInfo::MaxOffset) {
+                // If the start offset is out of bounds we clear both offsets
+                // so we only get the divot marker.  Error message will have to be reduced
+                // to line and column number.
+                startOffset = 0;
+                endOffset = 0;
+            } else if (endOffset > ExpressionRangeInfo::MaxOffset) {
+                // The end offset is only used for additional context, and is much more likely
+                // to overflow (eg. function call arguments) so we are willing to drop it without
+                // dropping the rest of the range.
+                endOffset = 0;
+            }
+            
+            ExpressionRangeInfo info;
+            info.instructionOffset = instructions().size();
+            info.divotPoint = divot;
+            info.startOffset = startOffset;
+            info.endOffset = endOffset;
+            m_codeBlock->expressionInfo.append(info);
+        }
+        
         ALWAYS_INLINE bool leftHandSideNeedsCopy(bool rightHasAssignments, bool rightIsPure)
         {
@@ -245 +274 @@
         RegisterID* emitPutSetter(RegisterID* base, const Identifier& property, RegisterID* value);
 
-        RegisterID* emitCall(RegisterID* dst, RegisterID* func, RegisterID* base, ArgumentsNode*);
-        RegisterID* emitCallEval(RegisterID* dst, RegisterID* func, RegisterID* base, ArgumentsNode*);
+        RegisterID* emitCall(RegisterID* dst, RegisterID* func, RegisterID* base, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
+        RegisterID* emitCallEval(RegisterID* dst, RegisterID* func, RegisterID* base, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
 
         RegisterID* emitReturn(RegisterID* src) { return emitUnaryNoDstOp(op_ret, src); } 
@@ -313 +342 @@
         typedef HashMap<RefPtr<UString::Rep>, int, IdentifierRepHash, HashTraits<RefPtr<UString::Rep> >, IdentifierMapIndexHashTraits> IdentifierMap;
 
-        RegisterID* emitCall(OpcodeID, RegisterID*, RegisterID*, RegisterID*, ArgumentsNode*);
+        RegisterID* emitCall(OpcodeID, RegisterID*, RegisterID*, RegisterID*, ArgumentsNode*, unsigned divot, unsigned startOffset, unsigned endOffset);
 
         // Maps a register index in the symbol table to a RegisterID index in m_locals.