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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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 jsopcodeinlines_h
#define jsopcodeinlines_h
#include "jsopcode.h"
#include "jsscript.h"
namespace js {
static inline unsigned
GetDefCount(JSScript* script, unsigned offset)
{
jsbytecode* pc = script->offsetToPC(offset);
/*
* Add an extra pushed value for OR/AND opcodes, so that they are included
* in the pushed array of stack values for type inference.
*/
switch (JSOp(*pc)) {
case JSOP_COALESCE:
case JSOP_OR:
case JSOP_AND:
return 1;
case JSOP_PICK:
case JSOP_UNPICK:
/*
* Pick pops and pushes how deep it looks in the stack + 1
* items. i.e. if the stack were |a b[2] c[1] d[0]|, pick 2
* would pop b, c, and d to rearrange the stack to |a c[0]
* d[1] b[2]|.
*/
return pc[1] + 1;
default:
return StackDefs(script, pc);
}
}
static inline unsigned
GetUseCount(JSScript* script, unsigned offset)
{
jsbytecode* pc = script->offsetToPC(offset);
if (JSOp(*pc) == JSOP_PICK || JSOp(*pc) == JSOP_UNPICK)
return pc[1] + 1;
if (CodeSpec[*pc].nuses == -1)
return StackUses(script, pc);
return CodeSpec[*pc].nuses;
}
static inline JSOp
ReverseCompareOp(JSOp op)
{
switch (op) {
case JSOP_GT:
return JSOP_LT;
case JSOP_GE:
return JSOP_LE;
case JSOP_LT:
return JSOP_GT;
case JSOP_LE:
return JSOP_GE;
case JSOP_EQ:
case JSOP_NE:
case JSOP_STRICTEQ:
case JSOP_STRICTNE:
return op;
default:
MOZ_CRASH("unrecognized op");
}
}
static inline JSOp
NegateCompareOp(JSOp op)
{
switch (op) {
case JSOP_GT:
return JSOP_LE;
case JSOP_GE:
return JSOP_LT;
case JSOP_LT:
return JSOP_GE;
case JSOP_LE:
return JSOP_GT;
case JSOP_EQ:
return JSOP_NE;
case JSOP_NE:
return JSOP_EQ;
case JSOP_STRICTNE:
return JSOP_STRICTEQ;
case JSOP_STRICTEQ:
return JSOP_STRICTNE;
default:
MOZ_CRASH("unrecognized op");
}
}
class BytecodeRange {
public:
BytecodeRange(JSContext* cx, JSScript* script)
: script(cx, script), pc(script->code()), end(pc + script->length())
{}
bool empty() const { return pc == end; }
jsbytecode* frontPC() const { return pc; }
JSOp frontOpcode() const { return JSOp(*pc); }
size_t frontOffset() const { return script->pcToOffset(pc); }
void popFront() { pc += GetBytecodeLength(pc); }
private:
RootedScript script;
jsbytecode* pc;
jsbytecode* end;
};
} // namespace js
#endif /* jsopcodeinlines_h */
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