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# HG changeset patch
# User Ted Campbell <[email protected]>
# Date 0 0
# Branch default
# Node ID 574ef3bd069f82d8a22da2313dc0c15832398def
# Parent  8e4a18a47c2f
Bug 1602530 - Add more asserts about bytecode structure. r?jorendorff


Depends on D58439

Differential Revision: https://phabricator.services.mozilla.com/D58441
diff --git a/js/src/vm/JSScript.h b/js/src/vm/JSScript.h
--- a/js/src/vm/JSScript.h
+++ b/js/src/vm/JSScript.h
@@ -3179,10 +3179,10 @@
   // The following 3 functions find the static scope just before the
   // execution of the instruction pointed to by pc.
 
-  js::Scope* lookupScope(jsbytecode* pc);
+  js::Scope* lookupScope(jsbytecode* pc) const;
 
-  js::Scope* innermostScope(jsbytecode* pc);
-  js::Scope* innermostScope() { return innermostScope(main()); }
+  js::Scope* innermostScope(jsbytecode* pc) const;
+  js::Scope* innermostScope() const { return innermostScope(main()); }
 
   /*
    * The isEmpty method tells whether this script has code that computes any
diff --git a/js/src/vm/JSScript.cpp b/js/src/vm/JSScript.cpp
--- a/js/src/vm/JSScript.cpp
+++ b/js/src/vm/JSScript.cpp
@@ -4561,6 +4561,12 @@
       MOZ_ASSERT_IF(target < loc, target.is(JSOP_LOOPHEAD));
       MOZ_ASSERT_IF(target < loc, IsBackedgePC(loc.toRawBytecode()));
 
+      // All forward jumps must be to a JSOP_JUMPTARGET op.
+      MOZ_ASSERT_IF(target > loc, target.is(JSOP_JUMPTARGET));
+
+      // Jumps must not cross scope boundaries.
+      MOZ_ASSERT(loc.innermostScope(this) == target.innermostScope(this));
+
       // Check fallthrough of conditional jump instructions.
       if (loc.fallsThrough()) {
         BytecodeLocation fallthrough = loc.next();
@@ -5375,7 +5381,7 @@
   return nlivefixed;
 }
 
-Scope* JSScript::lookupScope(jsbytecode* pc) {
+Scope* JSScript::lookupScope(jsbytecode* pc) const {
   MOZ_ASSERT(containsPC(pc));
 
   size_t offset = pc - code();
@@ -5424,7 +5430,7 @@
   return scope;
 }
 
-Scope* JSScript::innermostScope(jsbytecode* pc) {
+Scope* JSScript::innermostScope(jsbytecode* pc) const {
   if (Scope* scope = lookupScope(pc)) {
     return scope;
   }
diff --git a/js/src/vm/Interpreter.cpp b/js/src/vm/Interpreter.cpp
--- a/js/src/vm/Interpreter.cpp
+++ b/js/src/vm/Interpreter.cpp
@@ -1962,7 +1962,10 @@
     CASE(JSOP_LINENO)
     END_CASE(JSOP_LINENO)
 
-    CASE(JSOP_FORCEINTERPRETER)
+    CASE(JSOP_FORCEINTERPRETER) {
+      // Ensure pattern matching still works.
+      MOZ_ASSERT(script->hasForceInterpreterOp());
+    }
     END_CASE(JSOP_FORCEINTERPRETER)
 
     CASE(JSOP_UNDEFINED) {
diff --git a/js/src/vm/BytecodeLocation.h b/js/src/vm/BytecodeLocation.h
--- a/js/src/vm/BytecodeLocation.h
+++ b/js/src/vm/BytecodeLocation.h
@@ -90,6 +90,8 @@
 
   PropertyName* getPropertyName(const JSScript* script) const;
 
+  Scope* innermostScope(const JSScript* script) const;
+
 #ifdef DEBUG
   bool hasSameScript(const BytecodeLocation& other) const {
     return debugOnlyScript_ == other.debugOnlyScript_;
diff --git a/js/src/vm/BytecodeLocation-inl.h b/js/src/vm/BytecodeLocation-inl.h
--- a/js/src/vm/BytecodeLocation-inl.h
+++ b/js/src/vm/BytecodeLocation-inl.h
@@ -36,6 +36,11 @@
   return script->getName(this->rawBytecode_);
 }
 
+inline Scope* BytecodeLocation::innermostScope(const JSScript* script) const {
+  MOZ_ASSERT(this->isValid());
+  return script->innermostScope(this->rawBytecode_);
+}
+
 inline uint32_t BytecodeLocation::tableSwitchCaseOffset(
     const JSScript* script, uint32_t caseIndex) const {
   return script->tableSwitchCaseOffset(this->rawBytecode_, caseIndex);