webkitgtk-2.4.9webkitgtk-2.4.9

1 files changed, 134 insertions, 90 deletions

diff --git a/Source/JavaScriptCore/llint/LowLevelInterpreter.cpp b/Source/JavaScriptCore/llint/LowLevelInterpreter.cpp
index 72bcddf57..48148c6f4 100644
--- a/Source/JavaScriptCore/llint/LowLevelInterpreter.cpp
+++ b/Source/JavaScriptCore/llint/LowLevelInterpreter.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012, 2014 Apple Inc. All rights reserved.
+ * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -25,15 +25,19 @@
 
 #include "config.h"
 #include "LowLevelInterpreter.h"
+
+#if ENABLE(LLINT)
+
 #include "LLIntOfflineAsmConfig.h"
 #include <wtf/InlineASM.h>
 
-#if !ENABLE(JIT)
+#if ENABLE(LLINT_C_LOOP)
 #include "CodeBlock.h"
 #include "CommonSlowPaths.h"
 #include "LLIntCLoop.h"
 #include "LLIntSlowPaths.h"
-#include "JSCInlines.h"
+#include "Operations.h"
+#include "VMInspector.h"
 #include <wtf/Assertions.h>
 #include <wtf/MathExtras.h>
 
@@ -86,12 +90,6 @@ using namespace JSC::LLInt;
 #define OFFLINE_ASM_BEGIN
 #define OFFLINE_ASM_END
 
-#if ENABLE(OPCODE_TRACING)
-#define TRACE_OPCODE(opcode) dataLogF("   op %s\n", #opcode)
-#else
-#define TRACE_OPCODE(opcode)
-#endif
-
 // To keep compilers happy in case of unused labels, force usage of the label:
 #define USE_LABEL(label) \
     do { \
@@ -99,9 +97,7 @@ using namespace JSC::LLInt;
             goto label; \
     } while (false)
 
-#define OFFLINE_ASM_OPCODE_LABEL(opcode) DEFINE_OPCODE(opcode) USE_LABEL(opcode); TRACE_OPCODE(opcode);
-
-#define OFFLINE_ASM_GLOBAL_LABEL(label)  OFFLINE_ASM_GLUE_LABEL(label)
+#define OFFLINE_ASM_OPCODE_LABEL(opcode) DEFINE_OPCODE(opcode) USE_LABEL(opcode);
 
 #if ENABLE(COMPUTED_GOTO_OPCODES)
 #define OFFLINE_ASM_GLUE_LABEL(label)  label: USE_LABEL(label);
@@ -151,7 +147,6 @@ static void Double2Ints(double val, uint32_t& lo, uint32_t& hi)
 // pseudo register, as well as hides endianness differences.
 
 struct CLoopRegister {
-    CLoopRegister() { i = static_cast<intptr_t>(0xbadbeef0baddbeef); }
     union {
         intptr_t i;
         uintptr_t u;
@@ -217,15 +212,10 @@ struct CLoopRegister {
 #endif // !CPU(BIG_ENDIAN)
 #endif // !USE(JSVALUE64)
 
-        intptr_t* ip;
         int8_t* i8p;
         void* vp;
-        CallFrame* callFrame;
         ExecState* execState;
         void* instruction;
-        VM* vm;
-        JSCell* cell;
-        ProtoCallFrame* protoCallFrame;
         NativeFunction nativeFunc;
 #if USE(JSVALUE64)
         int64_t i64;
@@ -236,13 +226,6 @@ struct CLoopRegister {
         Opcode opcode;
     };
 
-    operator ExecState*() { return execState; }
-    operator Instruction*() { return reinterpret_cast<Instruction*>(instruction); }
-    operator VM*() { return vm; }
-    operator ProtoCallFrame*() { return protoCallFrame; }
-    operator Register*() { return reinterpret_cast<Register*>(vp); }
-    operator JSCell*() { return cell; }
-
 #if USE(JSVALUE64)
     inline void clearHighWord() { i32padding = 0; }
 #else
@@ -254,7 +237,7 @@ struct CLoopRegister {
 // The llint C++ interpreter loop:
 //
 
-JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm, ProtoCallFrame* protoCallFrame, bool isInitializationPass)
+JSValue CLoop::execute(CallFrame* callFrame, Opcode entryOpcode, bool isInitializationPass)
 {
     #define CAST reinterpret_cast
     #define SIGN_BIT32(x) ((x) & 0x80000000)
@@ -289,6 +272,8 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
         return JSValue();
     }
 
+    ASSERT(callFrame->vm().topCallFrame == callFrame);
+
     // Define the pseudo registers used by the LLINT C Loop backend:
     ASSERT(sizeof(CLoopRegister) == sizeof(intptr_t));
 
@@ -323,66 +308,69 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
     // 2. 32 bit result values will be in the low 32-bit of t0.
     // 3. 64 bit result values will be in t0.
 
-    CLoopRegister t0, t1, t2, t3, t5, t7, sp, cfr, lr, pc;
+    CLoopRegister t0, t1, t2, t3;
 #if USE(JSVALUE64)
-    CLoopRegister pcBase, tagTypeNumber, tagMask;
+    CLoopRegister rBasePC, tagTypeNumber, tagMask;
 #endif
+    CLoopRegister rRetVPC;
     CLoopDoubleRegister d0, d1;
 
-    lr.opcode = getOpcode(llint_return_to_host);
-    sp.vp = vm->interpreter->stack().topOfStack() + 1;
-    cfr.callFrame = vm->topCallFrame;
-#ifndef NDEBUG
-    void* startSP = sp.vp;
-    CallFrame* startCFR = cfr.callFrame;
-#endif
+    // Keep the compiler happy. We don't really need this, but the compiler
+    // will complain. This makes the warning go away.
+    t0.i = 0;
+    t1.i = 0;
 
-    // Initialize the incoming args for doVMEntryToJavaScript:
-    t0.vp = executableAddress;
-    t1.vm = vm;
-    t2.protoCallFrame = protoCallFrame;
+    VM* vm = &callFrame->vm();
+
+    CodeBlock* codeBlock = callFrame->codeBlock();
+    Instruction* vPC;
+
+    // rPC is an alias for vPC. Set up the alias:
+    CLoopRegister& rPC = *CAST<CLoopRegister*>(&vPC);
+
+#if USE(JSVALUE32_64)
+    vPC = codeBlock->instructions().begin();
+#else // USE(JSVALUE64)
+    vPC = 0;
+    rBasePC.vp = codeBlock->instructions().begin();
 
-#if USE(JSVALUE64)
     // For the ASM llint, JITStubs takes care of this initialization. We do
     // it explicitly here for the C loop:
     tagTypeNumber.i = 0xFFFF000000000000;
     tagMask.i = 0xFFFF000000000002;
 #endif // USE(JSVALUE64)
 
+    // cfr is an alias for callFrame. Set up this alias:
+    CLoopRegister& cfr = *CAST<CLoopRegister*>(&callFrame);
+
+    // Simulate a native return PC which should never be used:
+    rRetVPC.i = 0xbbadbeef;
+
     // Interpreter variables for value passing between opcodes and/or helpers:
     NativeFunction nativeFunc = 0;
     JSValue functionReturnValue;
-    Opcode opcode = getOpcode(entryOpcodeID);
+    Opcode opcode;
 
-#define PUSH(cloopReg) \
-    do { \
-        sp.ip--; \
-        *sp.ip = cloopReg.i; \
-    } while (false)
+    opcode = entryOpcode;
 
-#define POP(cloopReg) \
-    do { \
-        cloopReg.i = *sp.ip; \
-        sp.ip++; \
-    } while (false)
+    #if ENABLE(OPCODE_STATS)
+        #define RECORD_OPCODE_STATS(__opcode) \
+            OpcodeStats::recordInstruction(__opcode)
+    #else
+        #define RECORD_OPCODE_STATS(__opcode)
+    #endif
 
-#if ENABLE(OPCODE_STATS)
-#define RECORD_OPCODE_STATS(__opcode) OpcodeStats::recordInstruction(__opcode)
-#else
-#define RECORD_OPCODE_STATS(__opcode)
-#endif
+    #if USE(JSVALUE32_64)
+        #define FETCH_OPCODE() vPC->u.opcode
+    #else // USE(JSVALUE64)
+        #define FETCH_OPCODE() *bitwise_cast<Opcode*>(rBasePC.i8p + rPC.i * 8)
+    #endif // USE(JSVALUE64)
 
-#if USE(JSVALUE32_64)
-#define FETCH_OPCODE() pc.opcode
-#else // USE(JSVALUE64)
-#define FETCH_OPCODE() *bitwise_cast<Opcode*>(pcBase.i8p + pc.i * 8)
-#endif // USE(JSVALUE64)
-
-#define NEXT_INSTRUCTION() \
-    do {                         \
-        opcode = FETCH_OPCODE(); \
-        DISPATCH_OPCODE();       \
-    } while (false)
+    #define NEXT_INSTRUCTION() \
+        do {                         \
+            opcode = FETCH_OPCODE(); \
+            DISPATCH_OPCODE();       \
+        } while (false)
 
 #if ENABLE(COMPUTED_GOTO_OPCODES)
 
@@ -424,22 +412,14 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
 
         #include "LLIntAssembly.h"
 
-        OFFLINE_ASM_GLUE_LABEL(llint_return_to_host)
-        {
-            ASSERT(startSP == sp.vp);
-            ASSERT(startCFR == cfr.callFrame);
-#if USE(JSVALUE32_64)
-            return JSValue(t1.i, t0.i); // returning JSValue(tag, payload);
-#else
-            return JSValue::decode(t0.encodedJSValue);
-#endif
-        }
-
         // In the ASM llint, getHostCallReturnValue() is a piece of glue
-        // function provided by the JIT (see jit/JITOperations.cpp).
+        // function provided by the JIT (see dfg/DFGOperations.cpp).
         // We simulate it here with a pseduo-opcode handler.
         OFFLINE_ASM_GLUE_LABEL(getHostCallReturnValue)
         {
+            // The ASM part pops the frame:
+            callFrame = callFrame->callerFrame();
+
             // The part in getHostCallReturnValueWithExecState():
             JSValue result = vm->hostCallReturnValue;
 #if USE(JSVALUE32_64)
@@ -448,8 +428,12 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
 #else
             t0.encodedJSValue = JSValue::encode(result);
 #endif
-            opcode = lr.opcode;
-            DISPATCH_OPCODE();
+            goto doReturnHelper;
+        }
+
+        OFFLINE_ASM_GLUE_LABEL(returnFromJavaScript)
+        {
+            return vm->exception();
         }
 
 #if !ENABLE(COMPUTED_GOTO_OPCODES)
@@ -459,6 +443,55 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
 
     } // END bytecode handler cases.
 
+    //========================================================================
+    // Bytecode helpers:
+
+    doReturnHelper: {
+        ASSERT(!!callFrame);
+        if (callFrame->isVMEntrySentinel()) {
+#if USE(JSVALUE32_64)
+            return JSValue(t1.i, t0.i); // returning JSValue(tag, payload);
+#else
+            return JSValue::decode(t0.encodedJSValue);
+#endif
+        }
+
+        // The normal ASM llint call implementation returns to the caller as
+        // recorded in rRetVPC, and the caller would fetch the return address
+        // from ArgumentCount.tag() (see the dispatchAfterCall() macro used in
+        // the callTargetFunction() macro in the llint asm files).
+        //
+        // For the C loop, we don't have the JIT stub to do this work for us. So,
+        // we jump to llint_generic_return_point.
+
+        vPC = callFrame->currentVPC();
+
+#if USE(JSVALUE64)
+        // Based on LowLevelInterpreter64.asm's dispatchAfterCall():
+
+        // When returning from a native trampoline call, unlike the assembly
+        // LLInt, we can't simply return to the caller. In our case, we grab
+        // the caller's VPC and resume execution there. However, the caller's
+        // VPC returned by callFrame->currentVPC() is in the form of the real
+        // address of the target bytecode, but the 64-bit llint expects the
+        // VPC to be a bytecode offset. Hence, we need to map it back to a
+        // bytecode offset before we dispatch via the usual dispatch mechanism
+        // i.e. NEXT_INSTRUCTION():
+
+        codeBlock = callFrame->codeBlock();
+        ASSERT(codeBlock);
+        rPC.vp = callFrame->currentVPC();
+        rPC.i = rPC.i8p - reinterpret_cast<int8_t*>(codeBlock->instructions().begin());
+        rPC.i >>= 3;
+
+        rBasePC.vp = codeBlock->instructions().begin();
+#endif // USE(JSVALUE64)
+
+        goto llint_generic_return_point;
+
+    } // END doReturnHelper.
+
+
 #if ENABLE(COMPUTED_GOTO_OPCODES)
     // Keep the compiler happy so that it doesn't complain about unused
     // labels for the LLInt trampoline glue. The labels are automatically
@@ -478,40 +511,49 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
     #undef CAST
     #undef SIGN_BIT32
 
-    return JSValue(); // to suppress a compiler warning.
 } // Interpreter::llintCLoopExecute()
 
 } // namespace JSC
 
-#elif !OS(WINDOWS)
+#else // !ENABLE(LLINT_C_LOOP)
 
 //============================================================================
 // Define the opcode dispatch mechanism when using an ASM loop:
 //
 
 // These are for building an interpreter from generated assembly code:
+#if CPU(X86_64) && COMPILER(CLANG)
+#define OFFLINE_ASM_BEGIN   asm ( \
+    ".cfi_startproc\n"
+
+#define OFFLINE_ASM_END     \
+    ".cfi_endproc\n" \
+);
+#else
 #define OFFLINE_ASM_BEGIN   asm (
 #define OFFLINE_ASM_END     );
+#endif
 
-#define OFFLINE_ASM_OPCODE_LABEL(__opcode) OFFLINE_ASM_LOCAL_LABEL(llint_##__opcode)
-#define OFFLINE_ASM_GLUE_LABEL(__opcode)   OFFLINE_ASM_LOCAL_LABEL(__opcode)
+#define OFFLINE_ASM_OPCODE_LABEL(__opcode) OFFLINE_ASM_GLOBAL_LABEL(llint_##__opcode)
+#define OFFLINE_ASM_GLUE_LABEL(__opcode)   OFFLINE_ASM_GLOBAL_LABEL(__opcode)
 
 #if CPU(ARM_THUMB2)
 #define OFFLINE_ASM_GLOBAL_LABEL(label)          \
     ".text\n"                                    \
-    ".align 4\n"                                 \
     ".globl " SYMBOL_STRING(label) "\n"          \
     HIDE_SYMBOL(label) "\n"                      \
     ".thumb\n"                                   \
     ".thumb_func " THUMB_FUNC_PARAM(label) "\n"  \
     SYMBOL_STRING(label) ":\n"
-#elif CPU(ARM64)
+#elif CPU(X86_64) && COMPILER(CLANG)
 #define OFFLINE_ASM_GLOBAL_LABEL(label)         \
     ".text\n"                                   \
-    ".align 4\n"                                \
     ".globl " SYMBOL_STRING(label) "\n"         \
     HIDE_SYMBOL(label) "\n"                     \
-    SYMBOL_STRING(label) ":\n"
+    SYMBOL_STRING(label) ":\n"                  \
+    ".cfi_def_cfa rbp, 0\n"                     \
+    ".cfi_offset 16, 8\n"                       \
+    ".cfi_offset 6, 0\n"
 #else
 #define OFFLINE_ASM_GLOBAL_LABEL(label)         \
     ".text\n"                                   \
@@ -526,4 +568,6 @@ JSValue CLoop::execute(OpcodeID entryOpcodeID, void* executableAddress, VM* vm,
 // for the interpreter, as compiled from LowLevelInterpreter.asm.
 #include "LLIntAssembly.h"
 
-#endif // ENABLE(JIT)
+#endif // !ENABLE(LLINT_C_LOOP)
+
+#endif // ENABLE(LLINT)