Mercurial > projects > ldc
diff dmd/optimize.c @ 1:c53b6e3fe49a trunk
[svn r5] Initial commit. Most things are very rough.
author | lindquist |
---|---|
date | Sat, 01 Sep 2007 21:43:27 +0200 |
parents | |
children | 3cfcb944304e |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/dmd/optimize.c Sat Sep 01 21:43:27 2007 +0200 @@ -0,0 +1,750 @@ + +// Compiler implementation of the D programming language +// Copyright (c) 1999-2007 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 <ctype.h> +#include <assert.h> +#include <math.h> + +#if __DMC__ +#include <complex.h> +#endif + +#include "lexer.h" +#include "mtype.h" +#include "expression.h" +#include "declaration.h" +#include "aggregate.h" +#include "init.h" + + +#ifdef IN_GCC +#include "d-gcc-real.h" + +/* %% fix? */ +extern "C" bool real_isnan (const real_t *); +#endif + +static real_t zero; // work around DMC bug for now + + +/************************************* + * If expression is a variable with a const initializer, + * return that initializer. + */ + +Expression *fromConstInitializer(Expression *e1) +{ + //printf("fromConstInitializer(%s)\n", e1->toChars()); + if (e1->op == TOKvar) + { VarExp *ve = (VarExp *)e1; + VarDeclaration *v = ve->var->isVarDeclaration(); + if (v && v->isConst() && v->init) + { Expression *ei = v->init->toExpression(); + if (ei && ei->type) + e1 = ei; + } + } + return e1; +} + + +Expression *Expression::optimize(int result) +{ + //printf("Expression::optimize(result = x%x) %s\n", result, toChars()); + return this; +} + +Expression *VarExp::optimize(int result) +{ + if (result & WANTinterpret) + { + return fromConstInitializer(this); + } + return this; +} + +Expression *TupleExp::optimize(int result) +{ + for (size_t i = 0; i < exps->dim; i++) + { Expression *e = (Expression *)exps->data[i]; + + e = e->optimize(WANTvalue | (result & WANTinterpret)); + exps->data[i] = (void *)e; + } + return this; +} + +Expression *ArrayLiteralExp::optimize(int result) +{ + if (elements) + { + for (size_t i = 0; i < elements->dim; i++) + { Expression *e = (Expression *)elements->data[i]; + + e = e->optimize(WANTvalue | (result & WANTinterpret)); + elements->data[i] = (void *)e; + } + } + return this; +} + +Expression *AssocArrayLiteralExp::optimize(int result) +{ + assert(keys->dim == values->dim); + for (size_t i = 0; i < keys->dim; i++) + { Expression *e = (Expression *)keys->data[i]; + + e = e->optimize(WANTvalue | (result & WANTinterpret)); + keys->data[i] = (void *)e; + + e = (Expression *)values->data[i]; + e = e->optimize(WANTvalue | (result & WANTinterpret)); + values->data[i] = (void *)e; + } + return this; +} + +Expression *StructLiteralExp::optimize(int result) +{ + if (elements) + { + for (size_t i = 0; i < elements->dim; i++) + { Expression *e = (Expression *)elements->data[i]; + if (!e) + continue; + e = e->optimize(WANTvalue | (result & WANTinterpret)); + elements->data[i] = (void *)e; + } + } + return this; +} + +Expression *TypeExp::optimize(int result) +{ + return this; +} + +Expression *UnaExp::optimize(int result) +{ + e1 = e1->optimize(result); + return this; +} + +Expression *NegExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + if (e1->isConst() == 1) + { + e = Neg(type, e1); + } + else + e = this; + return e; +} + +Expression *ComExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + if (e1->isConst() == 1) + { + e = Com(type, e1); + } + else + e = this; + return e; +} + +Expression *NotExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + if (e1->isConst() == 1) + { + e = Not(type, e1); + } + else + e = this; + return e; +} + +Expression *BoolExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + if (e1->isConst() == 1) + { + e = Bool(type, e1); + } + else + e = this; + return e; +} + +Expression *AddrExp::optimize(int result) +{ Expression *e; + + //printf("AddrExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(result); + // Convert &*ex to ex + if (e1->op == TOKstar) + { Expression *ex; + + ex = ((PtrExp *)e1)->e1; + if (type->equals(ex->type)) + e = ex; + else + { + e = ex->copy(); + e->type = type; + } + return e; + } + if (e1->op == TOKvar) + { VarExp *ve = (VarExp *)e1; + if (!ve->var->isOut() && !ve->var->isRef() && + !ve->var->isImportedSymbol()) + { + e = new SymOffExp(loc, ve->var, 0); + e->type = type; + return e; + } + } + if (e1->op == TOKindex) + { // Convert &array[n] to &array+n + IndexExp *ae = (IndexExp *)e1; + + if (ae->e2->op == TOKint64 && ae->e1->op == TOKvar) + { + integer_t index = ae->e2->toInteger(); + VarExp *ve = (VarExp *)ae->e1; + if (ve->type->ty == Tsarray && ve->type->next->ty != Tbit + && !ve->var->isImportedSymbol()) + { + TypeSArray *ts = (TypeSArray *)ve->type; + integer_t dim = ts->dim->toInteger(); + if (index < 0 || index >= dim) + error("array index %jd is out of bounds [0..%jd]", index, dim); + e = new SymOffExp(loc, ve->var, index * ts->next->size()); + e->type = type; + return e; + } + } + } + return this; +} + +Expression *PtrExp::optimize(int result) +{ + //printf("PtrExp::optimize(result = x%x) %s\n", result, toChars()); + e1 = e1->optimize(result); + // Convert *&ex to ex + if (e1->op == TOKaddress) + { Expression *e; + Expression *ex; + + ex = ((AddrExp *)e1)->e1; + if (type->equals(ex->type)) + e = ex; + else + { + e = ex->copy(); + e->type = type; + } + return e; + } + // Constant fold *(&structliteral + offset) + if (e1->op == TOKadd) + { + Expression *e; + e = Ptr(type, e1); + if (e != EXP_CANT_INTERPRET) + return e; + } + + return this; +} + +Expression *CallExp::optimize(int result) +{ Expression *e = this; + + e1 = e1->optimize(result); + if (e1->op == TOKvar && result & WANTinterpret) + { + FuncDeclaration *fd = ((VarExp *)e1)->var->isFuncDeclaration(); + if (fd) + { + Expression *eresult = fd->interpret(NULL, arguments); + if (eresult) + e = eresult; + else if (result & WANTinterpret) + error("cannot evaluate %s at compile time", toChars()); + } + } + return e; +} + + +Expression *CastExp::optimize(int result) +{ + //printf("CastExp::optimize(result = %d) %s\n", result, toChars()); + //printf("from %s to %s\n", type->toChars(), to->toChars()); + //printf("from %s\n", type->toChars()); + //printf("type = %p\n", type); + assert(type); + enum TOK op1 = e1->op; + + e1 = e1->optimize(result); + if (result & WANTinterpret) + e1 = fromConstInitializer(e1); + + if ((e1->op == TOKstring || e1->op == TOKarrayliteral) && + (type->ty == Tpointer || type->ty == Tarray) && + type->next->equals(e1->type->next) + ) + { + e1->type = type; + return e1; + } + /* The first test here is to prevent infinite loops + */ + if (op1 != TOKarrayliteral && e1->op == TOKarrayliteral) + return e1->castTo(NULL, to); + if (e1->op == TOKnull && + (type->ty == Tpointer || type->ty == Tclass)) + { + e1->type = type; + return e1; + } + + if (result & WANTflags && type->ty == Tclass && e1->type->ty == Tclass) + { + // See if we can remove an unnecessary cast + ClassDeclaration *cdfrom; + ClassDeclaration *cdto; + int offset; + + cdfrom = e1->type->isClassHandle(); + cdto = type->isClassHandle(); + if (cdto->isBaseOf(cdfrom, &offset) && offset == 0) + { + e1->type = type; + return e1; + } + } + + Expression *e; + + if (e1->isConst()) + { + if (e1->op == TOKsymoff) + { + if (type->size() == e1->type->size() && + type->toBasetype()->ty != Tsarray) + { + e1->type = type; + return e1; + } + return this; + } + if (to->toBasetype()->ty == Tvoid) + e = this; + else + e = Cast(type, to, e1); + } + else + e = this; + return e; +} + +Expression *BinExp::optimize(int result) +{ + //printf("BinExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + return this; +} + +Expression *AddExp::optimize(int result) +{ Expression *e; + + //printf("AddExp::optimize(%s)\n", toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() && e2->isConst()) + { + if (e1->op == TOKsymoff && e2->op == TOKsymoff) + return this; + e = Add(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *MinExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() && e2->isConst()) + { + if (e2->op == TOKsymoff) + return this; + e = Min(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *MulExp::optimize(int result) +{ Expression *e; + + //printf("MulExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Mul(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *DivExp::optimize(int result) +{ Expression *e; + + //printf("DivExp::optimize(%s)\n", toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Div(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *ModExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Mod(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *ShlExp::optimize(int result) +{ Expression *e; + + //printf("ShlExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + e = this; + if (e2->isConst() == 1) + { + integer_t i2 = e2->toInteger(); + if (i2 < 0 || i2 > e1->type->size() * 8) + { error("shift left by %jd exceeds %zu", i2, e2->type->size() * 8); + e2 = new IntegerExp(0); + } + if (e1->isConst() == 1) + e = new IntegerExp(loc, e1->toInteger() << e2->toInteger(), type); + } + return e; +} + +Expression *ShrExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Shr(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *UshrExp::optimize(int result) +{ Expression *e; + + //printf("UshrExp::optimize() %s\n", toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Ushr(type, e1, e2); + } + else + e = this; + return e; +} + +Expression *AndExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + e = And(type, e1, e2); + else + e = this; + return e; +} + +Expression *OrExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + e = Or(type, e1, e2); + else + e = this; + return e; +} + +Expression *XorExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + e = Xor(type, e1, e2); + else + e = this; + return e; +} + +Expression *CommaExp::optimize(int result) +{ Expression *e; + + //printf("CommaExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(result & WANTinterpret); + e2 = e2->optimize(result); + if (!e1 || e1->op == TOKint64 || e1->op == TOKfloat64 || !e1->checkSideEffect(2)) + { + e = e2; + if (e) + e->type = type; + } + else + e = this; + //printf("-CommaExp::optimize(result = %d) %s\n", result, e->toChars()); + return e; +} + +Expression *ArrayLengthExp::optimize(int result) +{ Expression *e; + + //printf("ArrayLengthExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(WANTvalue | (result & WANTinterpret)); + e = this; + if (e1->op == TOKstring || e1->op == TOKarrayliteral || e1->op == TOKassocarrayliteral) + { + e = ArrayLength(type, e1); + } + return e; +} + +Expression *EqualExp::optimize(int result) +{ Expression *e; + + //printf("EqualExp::optimize(result = %x) %s\n", result, toChars()); + e1 = e1->optimize(WANTvalue | (result & WANTinterpret)); + e2 = e2->optimize(WANTvalue | (result & WANTinterpret)); + e = this; + + Expression *e1 = fromConstInitializer(this->e1); + Expression *e2 = fromConstInitializer(this->e2); + + e = Equal(op, type, e1, e2); + if (e == EXP_CANT_INTERPRET) + e = this; + return e; +} + +Expression *IdentityExp::optimize(int result) +{ Expression *e; + + //printf("IdentityExp::optimize(result = %d) %s\n", result, toChars()); + e1 = e1->optimize(WANTvalue | (result & WANTinterpret)); + e2 = e2->optimize(WANTvalue | (result & WANTinterpret)); + e = this; + + if (this->e1->isConst() && this->e2->isConst()) + { + e = Identity(op, type, this->e1, this->e2); + } + return e; +} + +Expression *IndexExp::optimize(int result) +{ Expression *e; + + //printf("IndexExp::optimize(result = %d) %s\n", result, toChars()); + Expression *e1 = this->e1->optimize(WANTvalue | (result & WANTinterpret)); + if (result & WANTinterpret) + e1 = fromConstInitializer(e1); + e2 = e2->optimize(WANTvalue | (result & WANTinterpret)); + e = Index(type, e1, e2); + if (e == EXP_CANT_INTERPRET) + e = this; + return e; +} + +Expression *SliceExp::optimize(int result) +{ Expression *e; + + //printf("SliceExp::optimize(result = %d) %s\n", result, toChars()); + e = this; + e1 = e1->optimize(WANTvalue | (result & WANTinterpret)); + if (!lwr) + { if (e1->op == TOKstring) + { // Convert slice of string literal into dynamic array + Type *t = e1->type->toBasetype(); + if (t->next) + e = e1->castTo(NULL, t->next->arrayOf()); + } + return e; + } + if (result & WANTinterpret) + e1 = fromConstInitializer(e1); + lwr = lwr->optimize(WANTvalue | (result & WANTinterpret)); + upr = upr->optimize(WANTvalue | (result & WANTinterpret)); + e = Slice(type, e1, lwr, upr); + if (e == EXP_CANT_INTERPRET) + e = this; + return e; +} + +Expression *AndAndExp::optimize(int result) +{ Expression *e; + + //printf("AndAndExp::optimize(%d) %s\n", result, toChars()); + e1 = e1->optimize(WANTflags | (result & WANTinterpret)); + e = this; + if (e1->isBool(FALSE)) + { + e = new CommaExp(loc, e1, new IntegerExp(loc, 0, type)); + e->type = type; + e = e->optimize(result); + } + else + { + e2 = e2->optimize(WANTflags | (result & WANTinterpret)); + if (result && e2->type->toBasetype()->ty == Tvoid && !global.errors) + error("void has no value"); + if (e1->isConst()) + { + if (e2->isConst()) + { int n1 = e1->isBool(1); + int n2 = e2->isBool(1); + + e = new IntegerExp(loc, n1 && n2, type); + } + else if (e1->isBool(TRUE)) + e = new BoolExp(loc, e2, type); + } + } + return e; +} + +Expression *OrOrExp::optimize(int result) +{ Expression *e; + + e1 = e1->optimize(WANTflags | (result & WANTinterpret)); + e = this; + if (e1->isBool(TRUE)) + { // Replace with (e1, 1) + e = new CommaExp(loc, e1, new IntegerExp(loc, 1, type)); + e->type = type; + e = e->optimize(result); + } + else + { + e2 = e2->optimize(WANTflags | (result & WANTinterpret)); + if (result && e2->type->toBasetype()->ty == Tvoid && !global.errors) + error("void has no value"); + if (e1->isConst()) + { + if (e2->isConst()) + { int n1 = e1->isBool(1); + int n2 = e2->isBool(1); + + e = new IntegerExp(loc, n1 || n2, type); + } + else if (e1->isBool(FALSE)) + e = new BoolExp(loc, e2, type); + } + } + return e; +} + +Expression *CmpExp::optimize(int result) +{ Expression *e; + + //printf("CmpExp::optimize() %s\n", toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + if (e1->isConst() == 1 && e2->isConst() == 1) + { + e = Cmp(op, type, this->e1, this->e2); + } + else + e = this; + return e; +} + +Expression *CatExp::optimize(int result) +{ Expression *e; + + //printf("CatExp::optimize(%d) %s\n", result, toChars()); + e1 = e1->optimize(result); + e2 = e2->optimize(result); + e = Cat(type, e1, e2); + if (e == EXP_CANT_INTERPRET) + e = this; + return e; +} + + +Expression *CondExp::optimize(int result) +{ Expression *e; + + econd = econd->optimize(WANTflags | (result & WANTinterpret)); + if (econd->isBool(TRUE)) + e = e1->optimize(result); + else if (econd->isBool(FALSE)) + e = e2->optimize(result); + else + { e1 = e1->optimize(result); + e2 = e2->optimize(result); + e = this; + } + return e; +} + +