diff options
Diffstat (limited to 'engines/sci/engine/vm.cpp')
| -rw-r--r-- | engines/sci/engine/vm.cpp | 67 |
1 files changed, 57 insertions, 10 deletions
diff --git a/engines/sci/engine/vm.cpp b/engines/sci/engine/vm.cpp index 111e17d0eb..7c3e5cb03d 100644 --- a/engines/sci/engine/vm.cpp +++ b/engines/sci/engine/vm.cpp @@ -54,6 +54,53 @@ int script_gc_interval = GC_INTERVAL; // Number of steps in between gcs // FIXME static bool breakpointWasHit = false; // FIXME: Avoid non-const global vars + +#define SCI_XS_CALLEE_LOCALS ((SegmentId)-1) + +/** + * Adds an entry to the top of the execution stack. + * + * @param[in] s The state with which to execute + * @param[in] pc The initial program counter + * @param[in] sp The initial stack pointer + * @param[in] objp Pointer to the beginning of the current object + * @param[in] argc Number of parameters to call with + * @param[in] argp Heap pointer to the first parameter + * @param[in] selector The selector by which it was called or + * NULL_SELECTOR if n.a. For debugging. + * @param[in] sendp Pointer to the object which the message was + * sent to. Equal to objp for anything but super. + * @param[in] origin Number of the execution stack element this + * entry was created by (usually the current TOS + * number, except for multiple sends). + * @param[in] local_segment The segment to use for local variables, + * or SCI_XS_CALLEE_LOCALS to use obj's segment. + * @return A pointer to the new exec stack TOS entry + */ +static ExecStack *add_exec_stack_entry(Common::List<ExecStack> &execStack, reg_t pc, StackPtr sp, + reg_t objp, int argc, StackPtr argp, Selector selector, + reg_t sendp, int origin, SegmentId local_segment); + + +/** + * Adds one varselector access to the execution stack. + * This function is called from send_selector only. + * @param[in] s The EngineState to use + * @param[in] objp Pointer to the object owning the selector + * @param[in] argc 1 for writing, 0 for reading + * @param[in] argp Pointer to the address of the data to write -2 + * @param[in] selector Selector name + * @param[in] address Heap address of the selector + * @param[in] origin Stack frame which the access originated from + * @return Pointer to the new exec-TOS element + */ +static ExecStack *add_exec_stack_varselector(Common::List<ExecStack> &execStack, reg_t objp, int argc, + StackPtr argp, Selector selector, const ObjVarRef& address, + int origin); + + + + // validation functionality #ifndef DISABLE_VALIDATIONS @@ -258,7 +305,7 @@ ExecStack *execute_method(EngineState *s, uint16 script, uint16 pubfunct, StackP } } - return add_exec_stack_entry(s, make_reg(seg, temp), sp, calling_obj, argc, argp, -1, calling_obj, s->_executionStack.size()-1, seg); + return add_exec_stack_entry(s->_executionStack, make_reg(seg, temp), sp, calling_obj, argc, argp, -1, calling_obj, s->_executionStack.size()-1, seg); } @@ -431,10 +478,10 @@ ExecStack *send_selector(EngineState *s, reg_t send_obj, reg_t work_obj, StackPt while (!sendCalls.empty()) { CallsStruct call = sendCalls.pop(); if (call.type == EXEC_STACK_TYPE_VARSELECTOR) // Write/read variable? - add_exec_stack_varselector(s, work_obj, call.argc, call.argp, + add_exec_stack_varselector(s->_executionStack, work_obj, call.argc, call.argp, call.selector, call.address.var, origin); else - add_exec_stack_entry(s, call.address.func, call.sp, work_obj, + add_exec_stack_entry(s->_executionStack, call.address.func, call.sp, work_obj, call.argc, call.argp, call.selector, send_obj, origin, SCI_XS_CALLEE_LOCALS); } @@ -446,8 +493,8 @@ ExecStack *send_selector(EngineState *s, reg_t send_obj, reg_t work_obj, StackPt return &(s->_executionStack.back()); } -ExecStack *add_exec_stack_varselector(EngineState *s, reg_t objp, int argc, StackPtr argp, Selector selector, const ObjVarRef& address, int origin) { - ExecStack *xstack = add_exec_stack_entry(s, NULL_REG, 0, objp, argc, argp, selector, objp, origin, SCI_XS_CALLEE_LOCALS); +static ExecStack *add_exec_stack_varselector(Common::List<ExecStack> &execStack, reg_t objp, int argc, StackPtr argp, Selector selector, const ObjVarRef& address, int origin) { + ExecStack *xstack = add_exec_stack_entry(execStack, NULL_REG, 0, objp, argc, argp, selector, objp, origin, SCI_XS_CALLEE_LOCALS); // Store selector address in sp xstack->addr.varp = address; @@ -456,7 +503,7 @@ ExecStack *add_exec_stack_varselector(EngineState *s, reg_t objp, int argc, Stac return xstack; } -ExecStack *add_exec_stack_entry(EngineState *s, reg_t pc, StackPtr sp, reg_t objp, int argc, +static ExecStack *add_exec_stack_entry(Common::List<ExecStack> &execStack, reg_t pc, StackPtr sp, reg_t objp, int argc, StackPtr argp, Selector selector, reg_t sendp, int origin, SegmentId _localsSegment) { // Returns new TOS element for the execution stack // _localsSegment may be -1 if derived from the called object @@ -486,8 +533,8 @@ ExecStack *add_exec_stack_entry(EngineState *s, reg_t pc, StackPtr sp, reg_t obj xstack.type = EXEC_STACK_TYPE_CALL; // Normal call - s->_executionStack.push_back(xstack); - return &(s->_executionStack.back()); + execStack.push_back(xstack); + return &(execStack.back()); } #ifdef DISABLE_VALIDATIONS @@ -982,7 +1029,7 @@ void run_vm(EngineState *s, bool restoring) { StackPtr call_base = scriptState.xs->sp - argc; scriptState.xs->sp[1].offset += scriptState.restAdjust; - xs_new = add_exec_stack_entry(s, make_reg(scriptState.xs->addr.pc.segment, + xs_new = add_exec_stack_entry(s->_executionStack, make_reg(scriptState.xs->addr.pc.segment, scriptState.xs->addr.pc.offset + opparams[0]), scriptState.xs->sp, scriptState.xs->objp, (validate_arithmetic(*call_base)) + scriptState.restAdjust, @@ -1026,7 +1073,7 @@ void run_vm(EngineState *s, bool restoring) { // This is useful in debugger backtraces if this // kernel function calls a script itself. ExecStack *xstack; - xstack = add_exec_stack_entry(s, NULL_REG, NULL, NULL_REG, argc, argv - 1, 0, NULL_REG, + xstack = add_exec_stack_entry(s->_executionStack, NULL_REG, NULL, NULL_REG, argc, argv - 1, 0, NULL_REG, s->_executionStack.size()-1, SCI_XS_CALLEE_LOCALS); xstack->selector = opparams[0]; xstack->type = EXEC_STACK_TYPE_KERNEL; |