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-rw-r--r--js/src/jit/BytecodeAnalysis.h78
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diff --git a/js/src/jit/BytecodeAnalysis.h b/js/src/jit/BytecodeAnalysis.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jit_BytecodeAnalysis_h
+#define jit_BytecodeAnalysis_h
+
+#include "jsscript.h"
+#include "jit/JitAllocPolicy.h"
+#include "js/Vector.h"
+
+namespace js {
+namespace jit {
+
+// Basic information about bytecodes in the script. Used to help baseline compilation.
+struct BytecodeInfo
+{
+ static const uint16_t MAX_STACK_DEPTH = 0xffffU;
+ uint16_t stackDepth;
+ bool initialized : 1;
+ bool jumpTarget : 1;
+
+ // If true, this is a JSOP_LOOPENTRY op inside a catch or finally block.
+ bool loopEntryInCatchOrFinally : 1;
+
+ void init(unsigned depth) {
+ MOZ_ASSERT(depth <= MAX_STACK_DEPTH);
+ MOZ_ASSERT_IF(initialized, stackDepth == depth);
+ initialized = true;
+ stackDepth = depth;
+ }
+};
+
+class BytecodeAnalysis
+{
+ JSScript* script_;
+ Vector<BytecodeInfo, 0, JitAllocPolicy> infos_;
+
+ bool usesEnvironmentChain_;
+ bool hasTryFinally_;
+ bool hasSetArg_;
+
+ public:
+ explicit BytecodeAnalysis(TempAllocator& alloc, JSScript* script);
+
+ MOZ_MUST_USE bool init(TempAllocator& alloc, GSNCache& gsn);
+
+ BytecodeInfo& info(jsbytecode* pc) {
+ MOZ_ASSERT(infos_[script_->pcToOffset(pc)].initialized);
+ return infos_[script_->pcToOffset(pc)];
+ }
+
+ BytecodeInfo* maybeInfo(jsbytecode* pc) {
+ if (infos_[script_->pcToOffset(pc)].initialized)
+ return &infos_[script_->pcToOffset(pc)];
+ return nullptr;
+ }
+
+ bool usesEnvironmentChain() const {
+ return usesEnvironmentChain_;
+ }
+
+ bool hasTryFinally() const {
+ return hasTryFinally_;
+ }
+
+ bool hasSetArg() const {
+ return hasSetArg_;
+ }
+};
+
+
+} // namespace jit
+} // namespace js
+
+#endif /* jit_BytecodeAnalysis_h */