// Copyright (c) 1999-2009 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// License for redistribution is by either the Artistic License
// in artistic.txt, or the GNU General Public License in gnu.txt.
// See the included readme.txt for details.

#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "rmem.h"

#include "stringtable.h"

#include "expression.h"
#include "statement.h"
#include "mtype.h"
#include "declaration.h"
#include "scope.h"
#include "id.h"
#include "module.h"
#include "init.h"

#if IN_DMD
extern int binary(const char *p , const char **tab, int high);

/**************************************
 * Hash table of array op functions already generated or known about.
 */

StringTable arrayfuncs;
#endif

/***********************************
 * Construct the array operation expression.
 */

Expression *BinExp::arrayOp(Scope *sc)
{
    Expressions *arguments = new Expressions();

    /* The expression to generate an array operation for is mangled
     * into a name to use as the array operation function name.
     * Mangle in the operands and operators in RPN order, and type.
     */
    OutBuffer buf;
    buf.writestring("_array");
    buildArrayIdent(&buf, arguments);
    buf.writeByte('_');

    /* Append deco of array element type
     */
#if DMDV2
    buf.writestring(type->toBasetype()->nextOf()->toBasetype()->mutableOf()->deco);
#else
    buf.writestring(type->toBasetype()->nextOf()->toBasetype()->deco);
#endif

    size_t namelen = buf.offset;
    buf.writeByte(0);
    char *name = (char *)buf.extractData();

    /* Look up name in hash table
     */
#if IN_LLVM
    StringValue *sv = sc->module->arrayfuncs.update(name, namelen);
#else
    StringValue *sv = arrayfuncs.update(name, namelen);
#endif
    FuncDeclaration *fd = (FuncDeclaration *)sv->ptrvalue;
    if (!fd)
    {
#if IN_DMD
	/* Some of the array op functions are written as library functions,
	 * presumably to optimize them with special CPU vector instructions.
	 * List those library functions here, in alpha order.
	 */
	static const char *libArrayopFuncs[] =
	{
	    "_arrayExpSliceAddass_a",
	    "_arrayExpSliceAddass_d",		// T[]+=T
	    "_arrayExpSliceAddass_f",		// T[]+=T
	    "_arrayExpSliceAddass_g",
	    "_arrayExpSliceAddass_h",
	    "_arrayExpSliceAddass_i",
	    "_arrayExpSliceAddass_k",
	    "_arrayExpSliceAddass_s",
	    "_arrayExpSliceAddass_t",
	    "_arrayExpSliceAddass_u",
	    "_arrayExpSliceAddass_w",

	    "_arrayExpSliceDivass_d",		// T[]/=T
	    "_arrayExpSliceDivass_f",		// T[]/=T

	    "_arrayExpSliceMinSliceAssign_a",
	    "_arrayExpSliceMinSliceAssign_d",	// T[]=T-T[]
	    "_arrayExpSliceMinSliceAssign_f",	// T[]=T-T[]
	    "_arrayExpSliceMinSliceAssign_g",
	    "_arrayExpSliceMinSliceAssign_h",
	    "_arrayExpSliceMinSliceAssign_i",
	    "_arrayExpSliceMinSliceAssign_k",
	    "_arrayExpSliceMinSliceAssign_s",
	    "_arrayExpSliceMinSliceAssign_t",
	    "_arrayExpSliceMinSliceAssign_u",
	    "_arrayExpSliceMinSliceAssign_w",

	    "_arrayExpSliceMinass_a",
	    "_arrayExpSliceMinass_d",		// T[]-=T
	    "_arrayExpSliceMinass_f",		// T[]-=T
	    "_arrayExpSliceMinass_g",
	    "_arrayExpSliceMinass_h",
	    "_arrayExpSliceMinass_i",
	    "_arrayExpSliceMinass_k",
	    "_arrayExpSliceMinass_s",
	    "_arrayExpSliceMinass_t",
	    "_arrayExpSliceMinass_u",
	    "_arrayExpSliceMinass_w",

	    "_arrayExpSliceMulass_d",		// T[]*=T
	    "_arrayExpSliceMulass_f",		// T[]*=T
	    "_arrayExpSliceMulass_i",
	    "_arrayExpSliceMulass_k",
	    "_arrayExpSliceMulass_s",
	    "_arrayExpSliceMulass_t",
	    "_arrayExpSliceMulass_u",
	    "_arrayExpSliceMulass_w",

	    "_arraySliceExpAddSliceAssign_a",
	    "_arraySliceExpAddSliceAssign_d",	// T[]=T[]+T
	    "_arraySliceExpAddSliceAssign_f",	// T[]=T[]+T
	    "_arraySliceExpAddSliceAssign_g",
	    "_arraySliceExpAddSliceAssign_h",
	    "_arraySliceExpAddSliceAssign_i",
	    "_arraySliceExpAddSliceAssign_k",
	    "_arraySliceExpAddSliceAssign_s",
	    "_arraySliceExpAddSliceAssign_t",
	    "_arraySliceExpAddSliceAssign_u",
	    "_arraySliceExpAddSliceAssign_w",

	    "_arraySliceExpDivSliceAssign_d",	// T[]=T[]/T
	    "_arraySliceExpDivSliceAssign_f",	// T[]=T[]/T

	    "_arraySliceExpMinSliceAssign_a",
	    "_arraySliceExpMinSliceAssign_d",	// T[]=T[]-T
	    "_arraySliceExpMinSliceAssign_f",	// T[]=T[]-T
	    "_arraySliceExpMinSliceAssign_g",
	    "_arraySliceExpMinSliceAssign_h",
	    "_arraySliceExpMinSliceAssign_i",
	    "_arraySliceExpMinSliceAssign_k",
	    "_arraySliceExpMinSliceAssign_s",
	    "_arraySliceExpMinSliceAssign_t",
	    "_arraySliceExpMinSliceAssign_u",
	    "_arraySliceExpMinSliceAssign_w",

	    "_arraySliceExpMulSliceAddass_d",	// T[] += T[]*T
	    "_arraySliceExpMulSliceAddass_f",
	    "_arraySliceExpMulSliceAddass_r",

	    "_arraySliceExpMulSliceAssign_d",	// T[]=T[]*T
	    "_arraySliceExpMulSliceAssign_f",	// T[]=T[]*T
	    "_arraySliceExpMulSliceAssign_i",
	    "_arraySliceExpMulSliceAssign_k",
	    "_arraySliceExpMulSliceAssign_s",
	    "_arraySliceExpMulSliceAssign_t",
	    "_arraySliceExpMulSliceAssign_u",
	    "_arraySliceExpMulSliceAssign_w",

	    "_arraySliceExpMulSliceMinass_d",	// T[] -= T[]*T
	    "_arraySliceExpMulSliceMinass_f",
	    "_arraySliceExpMulSliceMinass_r",

	    "_arraySliceSliceAddSliceAssign_a",
	    "_arraySliceSliceAddSliceAssign_d",	// T[]=T[]+T[]
	    "_arraySliceSliceAddSliceAssign_f",	// T[]=T[]+T[]
	    "_arraySliceSliceAddSliceAssign_g",
	    "_arraySliceSliceAddSliceAssign_h",
	    "_arraySliceSliceAddSliceAssign_i",
	    "_arraySliceSliceAddSliceAssign_k",
	    "_arraySliceSliceAddSliceAssign_r",	// T[]=T[]+T[]
	    "_arraySliceSliceAddSliceAssign_s",
	    "_arraySliceSliceAddSliceAssign_t",
	    "_arraySliceSliceAddSliceAssign_u",
	    "_arraySliceSliceAddSliceAssign_w",

	    "_arraySliceSliceAddass_a",
	    "_arraySliceSliceAddass_d",		// T[]+=T[]
	    "_arraySliceSliceAddass_f",		// T[]+=T[]
	    "_arraySliceSliceAddass_g",
	    "_arraySliceSliceAddass_h",
	    "_arraySliceSliceAddass_i",
	    "_arraySliceSliceAddass_k",
	    "_arraySliceSliceAddass_s",
	    "_arraySliceSliceAddass_t",
	    "_arraySliceSliceAddass_u",
	    "_arraySliceSliceAddass_w",

	    "_arraySliceSliceMinSliceAssign_a",
	    "_arraySliceSliceMinSliceAssign_d",	// T[]=T[]-T[]
	    "_arraySliceSliceMinSliceAssign_f",	// T[]=T[]-T[]
	    "_arraySliceSliceMinSliceAssign_g",
	    "_arraySliceSliceMinSliceAssign_h",
	    "_arraySliceSliceMinSliceAssign_i",
	    "_arraySliceSliceMinSliceAssign_k",
	    "_arraySliceSliceMinSliceAssign_r",	// T[]=T[]-T[]
	    "_arraySliceSliceMinSliceAssign_s",
	    "_arraySliceSliceMinSliceAssign_t",
	    "_arraySliceSliceMinSliceAssign_u",
	    "_arraySliceSliceMinSliceAssign_w",

	    "_arraySliceSliceMinass_a",
	    "_arraySliceSliceMinass_d",		// T[]-=T[]
	    "_arraySliceSliceMinass_f",		// T[]-=T[]
	    "_arraySliceSliceMinass_g",
	    "_arraySliceSliceMinass_h",
	    "_arraySliceSliceMinass_i",
	    "_arraySliceSliceMinass_k",
	    "_arraySliceSliceMinass_s",
	    "_arraySliceSliceMinass_t",
	    "_arraySliceSliceMinass_u",
	    "_arraySliceSliceMinass_w",

	    "_arraySliceSliceMulSliceAssign_d",	// T[]=T[]*T[]
	    "_arraySliceSliceMulSliceAssign_f",	// T[]=T[]*T[]
	    "_arraySliceSliceMulSliceAssign_i",
	    "_arraySliceSliceMulSliceAssign_k",
	    "_arraySliceSliceMulSliceAssign_s",
	    "_arraySliceSliceMulSliceAssign_t",
	    "_arraySliceSliceMulSliceAssign_u",
	    "_arraySliceSliceMulSliceAssign_w",

	    "_arraySliceSliceMulass_d",		// T[]*=T[]
	    "_arraySliceSliceMulass_f",		// T[]*=T[]
	    "_arraySliceSliceMulass_i",
	    "_arraySliceSliceMulass_k",
	    "_arraySliceSliceMulass_s",
	    "_arraySliceSliceMulass_t",
	    "_arraySliceSliceMulass_u",
	    "_arraySliceSliceMulass_w",
	};

	int i = binary(name, libArrayopFuncs, sizeof(libArrayopFuncs) / sizeof(char *));
	if (i == -1)
	{
#ifdef DEBUG	// Make sure our array is alphabetized
	    for (i = 0; i < sizeof(libArrayopFuncs) / sizeof(char *); i++)
	    {
		if (strcmp(name, libArrayopFuncs[i]) == 0)
		    assert(0);
	    }
#endif
#endif
	    /* Not in library, so generate it.
	     * Construct the function body:
	     *	foreach (i; 0 .. p.length)    for (size_t i = 0; i < p.length; i++)
	     *	    loopbody;
	     *	return p;
	     */

	    Arguments *fparams = new Arguments();
	    Expression *loopbody = buildArrayLoop(fparams);
	    Argument *p = (Argument *)fparams->data[0 /*fparams->dim - 1*/];
#if DMDV1
	    // for (size_t i = 0; i < p.length; i++)
	    Initializer *init = new ExpInitializer(0, new IntegerExp(0, 0, Type::tsize_t));
	    Dsymbol *d = new VarDeclaration(0, Type::tsize_t, Id::p, init);
	    Statement *s1 = new ForStatement(0,
		new DeclarationStatement(0, d),
		new CmpExp(TOKlt, 0, new IdentifierExp(0, Id::p), new ArrayLengthExp(0, new IdentifierExp(0, p->ident))),
		new PostExp(TOKplusplus, 0, new IdentifierExp(0, Id::p)),
		new ExpStatement(0, loopbody));
#else
	    // foreach (i; 0 .. p.length)
	    Statement *s1 = new ForeachRangeStatement(0, TOKforeach,
		new Argument(0, NULL, Id::p, NULL),
		new IntegerExp(0, 0, Type::tint32),
		new ArrayLengthExp(0, new IdentifierExp(0, p->ident)),
		new ExpStatement(0, loopbody));
#endif
	    Statement *s2 = new ReturnStatement(0, new IdentifierExp(0, p->ident));
	    //printf("s2: %s\n", s2->toChars());
	    Statement *fbody = new CompoundStatement(0, s1, s2);

	    /* Construct the function
	     */
	    TypeFunction *ftype = new TypeFunction(fparams, type, 0, LINKc);
	    //printf("ftype: %s\n", ftype->toChars());
	    fd = new FuncDeclaration(0, 0, Lexer::idPool(name), STCundefined, ftype);
	    fd->fbody = fbody;
	    fd->protection = PROTpublic;
	    fd->linkage = LINKd;

   		// special attention for array ops
        fd->isArrayOp = true;

	    sc->module->importedFrom->members->push(fd);

	    sc = sc->push();
	    sc->parent = sc->module->importedFrom;
	    sc->stc = 0;
	    sc->linkage = LINKc;
	    fd->semantic(sc);
	    sc->pop();
#if IN_DMD
	}
	else
	{   /* In library, refer to it.
	     */
	    fd = FuncDeclaration::genCfunc(type, name);
	}
#endif
	sv->ptrvalue = fd;	// cache symbol in hash table
    }

    /* Call the function fd(arguments)
     */
    Expression *ec = new VarExp(0, fd);
    Expression *e = new CallExp(loc, ec, arguments);
    e->type = type;
    return e;
}

/******************************************
 * Construct the identifier for the array operation function,
 * and build the argument list to pass to it.
 */

void Expression::buildArrayIdent(OutBuffer *buf, Expressions *arguments)
{
    buf->writestring("Exp");
    arguments->shift(this);
}

void SliceExp::buildArrayIdent(OutBuffer *buf, Expressions *arguments)
{
    buf->writestring("Slice");
    arguments->shift(this);
}

void AssignExp::buildArrayIdent(OutBuffer *buf, Expressions *arguments)
{
    /* Evaluate assign expressions right to left
     */
    e2->buildArrayIdent(buf, arguments);
    e1->buildArrayIdent(buf, arguments);
    buf->writestring("Assign");
}

#define X(Str) \
void Str##AssignExp::buildArrayIdent(OutBuffer *buf, Expressions *arguments) \
{							\
    /* Evaluate assign expressions right to left	\
     */							\
    e2->buildArrayIdent(buf, arguments);		\
    e1->buildArrayIdent(buf, arguments);		\
    buf->writestring(#Str);				\
    buf->writestring("ass");				\
}

X(Add)
X(Min)
X(Mul)
X(Div)
X(Mod)
X(Xor)
X(And)
X(Or)

#undef X

void NegExp::buildArrayIdent(OutBuffer *buf, Expressions *arguments)
{
    e1->buildArrayIdent(buf, arguments);
    buf->writestring("Neg");
}

void ComExp::buildArrayIdent(OutBuffer *buf, Expressions *arguments)
{
    e1->buildArrayIdent(buf, arguments);
    buf->writestring("Com");
}

#define X(Str) \
void Str##Exp::buildArrayIdent(OutBuffer *buf, Expressions *arguments)	\
{									\
    /* Evaluate assign expressions left to right			\
     */									\
    e1->buildArrayIdent(buf, arguments);				\
    e2->buildArrayIdent(buf, arguments);				\
    buf->writestring(#Str);						\
}

X(Add)
X(Min)
X(Mul)
X(Div)
X(Mod)
X(Xor)
X(And)
X(Or)

#undef X

/******************************************
 * Construct the inner loop for the array operation function,
 * and build the parameter list.
 */

Expression *Expression::buildArrayLoop(Arguments *fparams)
{
    Identifier *id = Identifier::generateId("c", fparams->dim);
    Argument *param = new Argument(0, type, id, NULL);
    fparams->shift(param);
    Expression *e = new IdentifierExp(0, id);
    return e;
}

Expression *SliceExp::buildArrayLoop(Arguments *fparams)
{
    Identifier *id = Identifier::generateId("p", fparams->dim);
    Argument *param = new Argument(STCconst, type, id, NULL);
    fparams->shift(param);
    Expression *e = new IdentifierExp(0, id);
    Expressions *arguments = new Expressions();
    Expression *index = new IdentifierExp(0, Id::p);
    arguments->push(index);
    e = new ArrayExp(0, e, arguments);
    return e;
}

Expression *AssignExp::buildArrayLoop(Arguments *fparams)
{
    /* Evaluate assign expressions right to left
     */
    Expression *ex2 = e2->buildArrayLoop(fparams);
    /* Need the cast because:
     *   b = c + p[i];
     * where b is a byte fails because (c + p[i]) is an int
     * which cannot be implicitly cast to byte.
     */
    ex2 = new CastExp(0, ex2, e1->type->nextOf());
    Expression *ex1 = e1->buildArrayLoop(fparams);
    Argument *param = (Argument *)fparams->data[0];
    param->storageClass = 0;
    Expression *e = new AssignExp(0, ex1, ex2);
    return e;
}

#define X(Str) \
Expression *Str##AssignExp::buildArrayLoop(Arguments *fparams)	\
{								\
    /* Evaluate assign expressions right to left		\
     */								\
    Expression *ex2 = e2->buildArrayLoop(fparams);		\
    Expression *ex1 = e1->buildArrayLoop(fparams);		\
    Argument *param = (Argument *)fparams->data[0];		\
    param->storageClass = 0;					\
    Expression *e = new Str##AssignExp(0, ex1, ex2);		\
    return e;							\
}

X(Add)
X(Min)
X(Mul)
X(Div)
X(Mod)
X(Xor)
X(And)
X(Or)

#undef X

Expression *NegExp::buildArrayLoop(Arguments *fparams)
{
    Expression *ex1 = e1->buildArrayLoop(fparams);
    Expression *e = new NegExp(0, ex1);
    return e;
}

Expression *ComExp::buildArrayLoop(Arguments *fparams)
{
    Expression *ex1 = e1->buildArrayLoop(fparams);
    Expression *e = new ComExp(0, ex1);
    return e;
}

#define X(Str) \
Expression *Str##Exp::buildArrayLoop(Arguments *fparams)	\
{								\
    /* Evaluate assign expressions left to right		\
     */								\
    Expression *ex1 = e1->buildArrayLoop(fparams);		\
    Expression *ex2 = e2->buildArrayLoop(fparams);		\
    Expression *e = new Str##Exp(0, ex1, ex2);			\
    return e;							\
}

X(Add)
X(Min)
X(Mul)
X(Div)
X(Mod)
X(Xor)
X(And)
X(Or)

#undef X