gered/picoc
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

Now stack frames appear on our new stack as they should. The old static

Browse source 
limits are gone.


git-svn-id: http://picoc.googlecode.com/svn/trunk@40 21eae674-98b7-11dd-bd71-f92a316d2d60
This commit is contained in:
zik.saleeba 2009-01-29 11:10:46 +00:00
parent 86cea880e3
commit b2396d3eda
3 changed files with 18 additions and 21 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
picoc.h
View file

@ -167,19 +167,17 @@ struct Table
/* stack frame for function calls */
struct StackFrame
{
struct LexState ReturnLex; /* how we got here */
struct Table LocalTable; /* the local variables and parameters */
struct LexState ReturnLex; /* how we got here */
struct Table LocalTable; /* the local variables and parameters */
struct TableEntry LocalHashTable[LOCAL_TABLE_SIZE];
struct StackFrame *PreviousStackFrame; /* the next lower stack frame */
};
/* globals */
extern struct Table GlobalTable;
extern struct LexState FunctionStore[FUNCTION_STORE_MAX];
extern int FunctionStoreUsed;
extern struct Value *Parameter[PARAMETER_MAX];
extern int ParameterUsed;
extern struct StackFrame Stack[STACK_MAX];
extern int StackUsed;
extern struct StackFrame *TopStackFrame;
extern struct Value *ReturnValue;
extern struct ValueType IntType;
extern struct ValueType CharType;

2
type.c
View file

@ -94,7 +94,7 @@ void TypeParseStruct(struct LexState *Lexer, struct ValueType **Typ, int IsStruc
if (LexGetPlainToken(Lexer) != TokenLeftBrace)
ProgramFail(Lexer, "'{' expected");
if (StackUsed != 0)
if (TopStackFrame != NULL)
ProgramFail(Lexer, "struct/union definitions can only be globals");
*Typ = TypeGetMatching(Lexer, &UberType, IsStruct ? TypeStruct : TypeUnion, 0, &LexValue->Val->String);

27
variable.c
View file

@ -7,14 +7,14 @@ struct Table GlobalTable;
struct TableEntry GlobalHashTable[GLOBAL_TABLE_SIZE];
/* the stack */
struct StackFrame Stack[STACK_MAX];
int StackUsed = 0;
struct StackFrame *TopStackFrame = NULL;
/* initialise the variable system */
void VariableInit()
{
TableInit(&GlobalTable, &GlobalHashTable[0], GLOBAL_TABLE_SIZE);
TopStackFrame = NULL;
}
/* allocate some memory, either on the heap or the stack and check if we've run out */
@ -64,7 +64,7 @@ struct Value *VariableAllocValueAndCopy(struct LexState *Lexer, struct Value *Fr
/* define a variable */
void VariableDefine(struct LexState *Lexer, const Str *Ident, struct Value *InitValue)
{
if (!TableSet((StackUsed == 0) ? &GlobalTable : &Stack[StackUsed-1].LocalTable, Ident, VariableAllocValueAndCopy(Lexer, InitValue, StackUsed == 0)))
if (!TableSet((TopStackFrame == NULL) ? &GlobalTable : &TopStackFrame->LocalTable, Ident, VariableAllocValueAndCopy(Lexer, InitValue, TopStackFrame == NULL)))
ProgramFail(Lexer, "'%S' is already defined", Ident);
}
@ -73,7 +73,7 @@ int VariableDefined(Str *Ident)
{
struct Value *FoundValue;
if (StackUsed == 0 || !TableGet(&Stack[StackUsed-1].LocalTable, Ident, &FoundValue))
if (TopStackFrame == NULL || !TableGet(&TopStackFrame->LocalTable, Ident, &FoundValue))
{
if (!TableGet(&GlobalTable, Ident, &FoundValue))
return FALSE;
@ -85,7 +85,7 @@ int VariableDefined(Str *Ident)
/* get the value of a variable. must be defined */
void VariableGet(struct LexState *Lexer, Str *Ident, struct Value **LVal)
{
if (StackUsed == 0 || !TableGet(&Stack[StackUsed-1].LocalTable, Ident, LVal))
if (TopStackFrame == NULL || !TableGet(&TopStackFrame->LocalTable, Ident, LVal))
{
if (!TableGet(&GlobalTable, Ident, LVal))
ProgramFail(Lexer, "'%S' is undefined", Ident);
@ -114,24 +114,23 @@ void VariableStackPop(struct LexState *Lexer, struct Value *Var)
/* add a stack frame when doing a function call */
void VariableStackFrameAdd(struct LexState *Lexer)
{
struct StackFrame *NewFrame = &Stack[StackUsed];
struct StackFrame *NewFrame;
if (StackUsed >= STACK_MAX)
ProgramFail(Lexer, "too many nested function calls");
HeapPushStackFrame();
NewFrame = HeapAllocStack(sizeof(struct StackFrame));
NewFrame->ReturnLex = *Lexer;
TableInit(&NewFrame->LocalTable, &NewFrame->LocalHashTable[0], LOCAL_TABLE_SIZE);
StackUsed++;
HeapPushStackFrame();
NewFrame->PreviousStackFrame = TopStackFrame;
TopStackFrame = NewFrame;
}
/* remove a stack frame */
void VariableStackFramePop(struct LexState *Lexer)
{
if (StackUsed == 0)
if (TopStackFrame == NULL)
ProgramFail(Lexer, "stack is empty - can't go back");
StackUsed--;
*Lexer = Stack[StackUsed].ReturnLex;
TopStackFrame = TopStackFrame->PreviousStackFrame;
*Lexer = TopStackFrame->ReturnLex;
HeapPopStackFrame();
}