X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2FSDCCopt.c;h=af7d6b6d2e9bf456e6e98ea4c03fc4d2e67ec7d3;hb=5267792e9b31120c7845fa888787b41bcdc5b38e;hp=34e0e78a7a92ac95c82346bbe6ba9cf69b2ab409;hpb=0ffd5b8214ce00fda7ad9b7aa08d9c7e920f540f;p=fw%2Fsdcc diff --git a/src/SDCCopt.c b/src/SDCCopt.c index 34e0e78a..af7d6b6d 100644 --- a/src/SDCCopt.c +++ b/src/SDCCopt.c @@ -176,6 +176,23 @@ cnvToFcall (iCode * ic, eBBlock * ebp) IC_RESULT (newic) = IC_RESULT (ic); newic->lineno = lineno; newic->parmBytes+=bytesPushed; + ebp->hasFcall = 1; + if (currFunc) + FUNC_HASFCALL (currFunc->type) = 1; + + if(TARGET_IS_PIC16) { + /* normally these functions aren't marked external, so we can use their + * _extern field to marked as already added to symbol table */ + + if(!SPEC_EXTR(func->etype)) { + memmap *seg = SPEC_OCLS(OP_SYMBOL(IC_LEFT(newic))->etype); + + SPEC_EXTR(func->etype) = 1; + seg = SPEC_OCLS( func->etype ); + addSet(&seg->syms, func); + } + } + addiCodeToeBBlock (ebp, newic, ip); } @@ -250,9 +267,25 @@ found: newic = newiCode (CALL, operandFromSymbol (func), NULL); IC_RESULT (newic) = IC_RESULT (ic); newic->parmBytes+=bytesPushed; + ebp->hasFcall = 1; + if (currFunc) + FUNC_HASFCALL (currFunc->type) = 1; + + if(TARGET_IS_PIC16) { + /* normally these functions aren't marked external, so we can use their + * _extern field to marked as already added to symbol table */ + + if(!SPEC_EXTR(func->etype)) { + memmap *seg = SPEC_OCLS(OP_SYMBOL(IC_LEFT(newic))->etype); + + SPEC_EXTR(func->etype) = 1; + seg = SPEC_OCLS( func->etype ); + addSet(&seg->syms, func); + } + } + addiCodeToeBBlock (ebp, newic, ip); newic->lineno = linenno; - } /*-----------------------------------------------------------------*/ @@ -327,9 +360,25 @@ found: newic = newiCode (CALL, operandFromSymbol (func), NULL); IC_RESULT (newic) = IC_RESULT (ic); newic->parmBytes+=bytesPushed; + ebp->hasFcall = 1; + if (currFunc) + FUNC_HASFCALL (currFunc->type) = 1; + + if(TARGET_IS_PIC16) { + /* normally these functions aren't marked external, so we can use their + * _extern field to marked as already added to symbol table */ + + if(!SPEC_EXTR(func->etype)) { + memmap *seg = SPEC_OCLS(OP_SYMBOL(IC_LEFT(newic))->etype); + + SPEC_EXTR(func->etype) = 1; + seg = SPEC_OCLS( func->etype ); + addSet(&seg->syms, func); + } + } + addiCodeToeBBlock (ebp, newic, ip); newic->lineno = lineno; - } extern operand *geniCodeRValue (operand *, bool); @@ -348,34 +397,8 @@ convilong (iCode * ic, eBBlock * ebp, sym_link * type, int op) int su; int bytesPushed=0; - // Easy special case which avoids function call: modulo by a literal power - // of two can be replaced by a bitwise AND. - if (op == '%' && isOperandLiteral(IC_RIGHT(ic))) - { - unsigned litVal = (unsigned)(operandLitValue(IC_RIGHT(ic))); - - // See if literal value is a power of 2. - while (litVal && !(litVal & 1)) - { - litVal >>= 1; - } - if (litVal) - { - // discard first high bit set. - litVal >>= 1; - } - - if (!litVal) - { - ic->op = BITWISEAND; - IC_RIGHT(ic) = operandFromLit(operandLitValue(IC_RIGHT(ic)) - 1); - return; - } - } - remiCodeFromeBBlock (ebp, ic); - /* depending on the type */ for (bwd = 0; bwd < 3; bwd++) { @@ -477,6 +500,23 @@ found: IC_RESULT (newic) = IC_RESULT (ic); newic->lineno = lineno; newic->parmBytes+=bytesPushed; // to clear the stack after the call + ebp->hasFcall = 1; + if (currFunc) + FUNC_HASFCALL (currFunc->type) = 1; + + if(TARGET_IS_PIC16) { + /* normally these functions aren't marked external, so we can use their + * _extern field to marked as already added to symbol table */ + + if(!SPEC_EXTR(func->etype)) { + memmap *seg = SPEC_OCLS(OP_SYMBOL(IC_LEFT(newic))->etype); + + SPEC_EXTR(func->etype) = 1; + seg = SPEC_OCLS( func->etype ); + addSet(&seg->syms, func); + } + } + addiCodeToeBBlock (ebp, newic, ip); } @@ -516,6 +556,32 @@ convertToFcall (eBBlock ** ebbs, int count) cnvToFloatCast (ic, ebbs[i]); } + // Easy special case which avoids function call: modulo by a literal power + // of two can be replaced by a bitwise AND. + if (ic->op == '%' && isOperandLiteral(IC_RIGHT(ic)) && + IS_UNSIGNED(operandType(IC_LEFT(ic)))) + { + unsigned litVal = abs(operandLitValue(IC_RIGHT(ic))); + + // See if literal value is a power of 2. + while (litVal && !(litVal & 1)) + { + litVal >>= 1; + } + if (litVal) + { + // discard lowest set bit. + litVal >>= 1; + } + + if (!litVal) + { + ic->op = BITWISEAND; + IC_RIGHT(ic) = operandFromLit(operandLitValue(IC_RIGHT(ic)) - 1); + continue; + } + } + /* if long / int mult or divide or mod */ if (ic->op == '*' || ic->op == '/' || ic->op == '%') { @@ -550,6 +616,31 @@ convertToFcall (eBBlock ** ebbs, int count) } } +/*-----------------------------------------------------------------*/ +/* isLocalWithoutDef - return 1 if sym might be used without a */ +/* defining iCode */ +/*-----------------------------------------------------------------*/ +static int +isLocalWithoutDef (symbol * sym) +{ + if (!IS_AUTO (sym)) + return 0; + + if (IS_VOLATILE (sym->type)) + return 0; + + if (sym->_isparm) + return 0; + + if (IS_AGGREGATE (sym->type)) + return 0; + + if (sym->addrtaken) + return 0; + + return !sym->defs; +} + /*-----------------------------------------------------------------*/ /* replaceRegEqv - replace all local variables with their reqv */ /*-----------------------------------------------------------------*/ @@ -558,6 +649,12 @@ replaceRegEqv (eBBlock ** ebbs, int count) { int i; + /* Update the symbols' def bitvector so we know if there is */ + /* a defining iCode or not. Only replace a local variable */ + /* with its register equivalent if there is a defining iCode; */ + /* otherwise, the port's register allocater may choke. */ + cseAllBlocks (ebbs, count, TRUE); + for (i = 0; i < count; i++) { @@ -571,7 +668,17 @@ replaceRegEqv (eBBlock ** ebbs, int count) if (ic->op == IFX) { - + if (IC_COND (ic) && + IS_TRUE_SYMOP (IC_COND (ic)) && + isLocalWithoutDef (OP_SYMBOL (IC_COND (ic)))) + { + werrorfl (ic->filename, ic->lineno, + W_LOCAL_NOINIT, + OP_SYMBOL (IC_COND (ic))->name); + OP_REQV (IC_COND (ic)) = NULL; + OP_SYMBOL (IC_COND (ic))->allocreq = 1; + } + if (IS_TRUE_SYMOP (IC_COND (ic)) && OP_REQV (IC_COND (ic))) IC_COND (ic) = opFromOpWithDU (OP_REQV (IC_COND (ic)), @@ -581,8 +688,20 @@ replaceRegEqv (eBBlock ** ebbs, int count) continue; } + if (ic->op == JUMPTABLE) { + if (IC_JTCOND (ic) && + IS_TRUE_SYMOP (IC_JTCOND (ic)) && + isLocalWithoutDef (OP_SYMBOL (IC_JTCOND (ic)))) + { + werrorfl (ic->filename, ic->lineno, + W_LOCAL_NOINIT, + OP_SYMBOL (IC_JTCOND (ic))->name); + OP_REQV (IC_JTCOND (ic)) = NULL; + OP_SYMBOL (IC_JTCOND (ic))->allocreq = 1; + } + if (IS_TRUE_SYMOP (IC_JTCOND (ic)) && OP_REQV (IC_JTCOND (ic))) IC_JTCOND (ic) = opFromOpWithDU (OP_REQV (IC_JTCOND (ic)), @@ -615,6 +734,17 @@ replaceRegEqv (eBBlock ** ebbs, int count) OP_SYMBOL (IC_RESULT (ic))->uses); } + if (IC_RIGHT (ic) && + IS_TRUE_SYMOP (IC_RIGHT (ic)) && + isLocalWithoutDef (OP_SYMBOL (IC_RIGHT (ic)))) + { + werrorfl (ic->filename, ic->lineno, + W_LOCAL_NOINIT, + OP_SYMBOL (IC_RIGHT (ic))->name); + OP_REQV (IC_RIGHT (ic)) = NULL; + OP_SYMBOL (IC_RIGHT (ic))->allocreq = 1; + } + if (IC_RIGHT (ic) && IS_TRUE_SYMOP (IC_RIGHT (ic)) && OP_REQV (IC_RIGHT (ic))) @@ -625,6 +755,17 @@ replaceRegEqv (eBBlock ** ebbs, int count) IC_RIGHT (ic)->isaddr = 0; } + if (IC_LEFT (ic) && + IS_TRUE_SYMOP (IC_LEFT (ic)) && + isLocalWithoutDef (OP_SYMBOL (IC_LEFT (ic)))) + { + werrorfl (ic->filename, ic->lineno, + W_LOCAL_NOINIT, + OP_SYMBOL (IC_LEFT (ic))->name); + OP_REQV (IC_LEFT (ic)) = NULL; + OP_SYMBOL (IC_LEFT (ic))->allocreq = 1; + } + if (IC_LEFT (ic) && IS_TRUE_SYMOP (IC_LEFT (ic)) && OP_REQV (IC_LEFT (ic))) @@ -638,6 +779,51 @@ replaceRegEqv (eBBlock ** ebbs, int count) } } +/*-----------------------------------------------------------------*/ +/* findReqv - search for a register equivalent */ +/*-----------------------------------------------------------------*/ +operand * +findReqv (symbol * prereqv, eBBlock ** ebbs, int count) +{ + int i; + iCode * ic; + + /* for all blocks do */ + for (i=0; isch; ic; ic = ic->next) + { + if (ic->op == IFX) + { + if (IS_ITEMP (IC_COND (ic)) + && OP_SYMBOL (IC_COND (ic))->prereqv == prereqv) + return IC_COND (ic); + } + else if (ic->op == JUMPTABLE) + { + if (IS_ITEMP (IC_JTCOND (ic)) + && OP_SYMBOL (IC_JTCOND (ic))->prereqv == prereqv) + return IC_JTCOND (ic); + } + else + { + if (IS_ITEMP (IC_LEFT (ic)) + && OP_SYMBOL (IC_LEFT (ic))->prereqv == prereqv) + return IC_LEFT (ic); + if (IS_ITEMP (IC_RIGHT (ic)) + && OP_SYMBOL (IC_RIGHT (ic))->prereqv == prereqv) + return IC_RIGHT (ic); + if (IS_ITEMP (IC_RESULT (ic)) + && OP_SYMBOL (IC_RESULT (ic))->prereqv == prereqv) + return IC_RESULT (ic); + } + } + } + + return NULL; +} + /*-----------------------------------------------------------------*/ /* killDeadCode - eliminates dead assignments */ /*-----------------------------------------------------------------*/ @@ -679,16 +865,35 @@ killDeadCode (eBBlock ** ebbs, int count) if (SKIP_IC (ic) || ic->op == IFX || - ic->op == RETURN) + ic->op == RETURN || + ic->op == DUMMY_READ_VOLATILE || + ic->op == CRITICAL || + ic->op == ENDCRITICAL) continue; + /* Since both IFX & JUMPTABLE (in SKIP_IC) have been tested for */ + /* it is now safe to assume IC_LEFT, IC_RIGHT, & IC_RESULT are */ + /* valid. */ + /* if the result is volatile then continue */ if (IC_RESULT (ic) && isOperandVolatile (IC_RESULT (ic), FALSE)) continue; + /* We also cannot remove the iCode, when an operand is volatile. */ + /* Even read access can cause side effects on some hardware registers! */ + + /* if the left operand is volatile then continue */ + if (IC_LEFT(ic) && isOperandVolatile (IC_LEFT (ic), TRUE)) + continue; + + /* if the result is a temp & isaddr then skip */ if (IC_RESULT (ic) && POINTER_SET (ic)) continue; + + if (POINTER_GET (ic) && IS_VOLATILE (operandType (IC_LEFT (ic))->next) + && !SPIL_LOC (IC_RESULT (ic))) + continue; /* if the result is used in the remainder of the */ /* block then skip */ @@ -725,17 +930,45 @@ killDeadCode (eBBlock ** ebbs, int count) continue; kill = 1; - } + } kill: /* kill this one if required */ if (kill) { + bool volLeft = IS_SYMOP (IC_LEFT (ic)) + && isOperandVolatile (IC_LEFT (ic), FALSE); + bool volRight = IS_SYMOP (IC_RIGHT (ic)) + && isOperandVolatile (IC_RIGHT (ic), FALSE); + + /* a dead address-of operation should die, even if volatile */ + if (ic->op == ADDRESS_OF) + volLeft = FALSE; + + if (ic->next && ic->seqPoint == ic->next->seqPoint + && (ic->next->op == '+' || ic->next->op == '-')) + { + if (isOperandEqual (IC_LEFT(ic), IC_LEFT(ic->next)) + || isOperandEqual (IC_LEFT(ic), IC_RIGHT(ic->next))) + volLeft = FALSE; + if (isOperandEqual (IC_RIGHT(ic), IC_LEFT(ic->next)) + || isOperandEqual (IC_RIGHT(ic), IC_RIGHT(ic->next))) + volRight = FALSE; + } + + if (POINTER_GET (ic) && IS_VOLATILE (operandType (IC_LEFT (ic))->next)) + { + if (SPIL_LOC (IC_RESULT (ic))) + { + IC_RESULT (ic) = newiTempFromOp (IC_RESULT (ic)); + SPIL_LOC (IC_RESULT (ic)) = NULL; + } + continue; + } + change = 1; gchange++; - /* eliminate this */ - remiCodeFromeBBlock (ebbs[i], ic); - + /* now delete from defUseSet */ deleteItemIf (&ebbs[i]->outExprs, ifDiCodeIsX, ic); bitVectUnSetBit (ebbs[i]->outDefs, ic->key); @@ -743,12 +976,56 @@ killDeadCode (eBBlock ** ebbs, int count) /* and defset of the block */ bitVectUnSetBit (ebbs[i]->defSet, ic->key); - /* for the left & right remove the usage */ - if (IS_SYMOP (IC_LEFT (ic))) - bitVectUnSetBit (OP_USES (IC_LEFT (ic)), ic->key); + /* If this is the last of a register equivalent, */ + /* look for a successor register equivalent. */ + bitVectUnSetBit (OP_DEFS (IC_RESULT (ic)), ic->key); + if (IS_ITEMP (IC_RESULT (ic)) + && OP_SYMBOL (IC_RESULT (ic))->isreqv + && bitVectIsZero (OP_DEFS (IC_RESULT (ic)))) + { + symbol * resultsym = OP_SYMBOL (IC_RESULT (ic)); + symbol * prereqv = resultsym->prereqv; + + if (OP_SYMBOL (prereqv->reqv) == resultsym) + { + operand * newreqv; + + IC_RESULT (ic) = NULL; + newreqv = findReqv (prereqv, ebbs, count); + if (newreqv) + { + prereqv->reqv = newreqv; + } + } + } + + /* delete the result */ + IC_RESULT (ic) = NULL; + + if (volLeft || volRight) + { + /* something is volatile, so keep the iCode */ + /* and change the operator instead */ + ic->op = DUMMY_READ_VOLATILE; + + /* keep only the volatile operands */ + if (!volLeft) + IC_LEFT (ic) = NULL; + if (!volRight) + IC_RIGHT (ic) = NULL; + } + else + { + /* nothing is volatile, eliminate the iCode */ + remiCodeFromeBBlock (ebbs[i], ic); + + /* for the left & right remove the usage */ + if (IS_SYMOP (IC_LEFT (ic))) + bitVectUnSetBit (OP_USES (IC_LEFT (ic)), ic->key); - if (IS_SYMOP (IC_RIGHT (ic))) - bitVectUnSetBit (OP_USES (IC_RIGHT (ic)), ic->key); + if (IS_SYMOP (IC_RIGHT (ic))) + bitVectUnSetBit (OP_USES (IC_RIGHT (ic)), ic->key); + } } } /* end of all instructions */ @@ -814,6 +1091,76 @@ discardDeadParamReceives (eBBlock ** ebbs, int count) } } +/*-----------------------------------------------------------------*/ +/* optimizeCastCast - remove unneeded intermediate casts. */ +/* Integer promotion may cast (un)signed char to int and then */ +/* recast the int to (un)signed long. If the signedness of the */ +/* char and long are the same, the cast can be safely performed in */ +/* a single step. */ +/*-----------------------------------------------------------------*/ +static void +optimizeCastCast (eBBlock ** ebbs, int count) +{ + int i; + iCode *ic; + iCode *uic; + sym_link * type1; + sym_link * type2; + sym_link * type3; + symbol * sym; + + for (i = 0; i < count; i++) + { + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + + if (ic->op == CAST && IC_RESULT (ic) && IS_ITEMP (IC_RESULT (ic))) + { + type1 = operandType (IC_RIGHT (ic)); + type2 = operandType (IC_RESULT (ic)); + + /* Look only for a cast from an integer type to an */ + /* integer type that has no loss of bits */ + if (!IS_INTEGRAL (type1) || !IS_INTEGRAL (type2)) + continue; + if (getSize (type2) < getSize (type1)) + continue; + + /* There must be only one use of this first result */ + if (bitVectnBitsOn (OP_USES (IC_RESULT (ic))) != 1) + continue; + + /* This use must be a second cast */ + uic = hTabItemWithKey (iCodehTab, + bitVectFirstBit (OP_USES (IC_RESULT (ic)))); + if (!uic || uic->op != CAST) + continue; + + /* It must be a cast to another integer type that */ + /* has no loss of bits */ + type3 = operandType (IC_RESULT (uic)); + if (!IS_INTEGRAL (type3)) + continue; + if (getSize (type3) < getSize (type2)) + continue; + + /* The signedness between the first and last types */ + /* must match */ + if (SPEC_USIGN (type3) != SPEC_USIGN (type1)) + continue; + + /* Change the first cast to a simple assignment and */ + /* let the second cast do all the work */ + ic->op = '='; + IC_LEFT (ic) = NULL; + sym = OP_SYMBOL (IC_RESULT (ic)); + sym->type = copyLinkChain (type1); + sym->etype = getSpec (sym->type); + } + } + } +} + /*-----------------------------------------------------------------*/ /* eBBlockFromiCode - creates extended basic blocks from iCode */ /* will return an array of eBBlock pointers */ @@ -845,6 +1192,12 @@ eBBlockFromiCode (iCode * ic) ebbs = iCodeBreakDown (ic, &count); saveCount = count; + /* hash the iCode keys so that we can quickly index */ + /* them in the rest of the optimization steps */ + setToNull ((void *) &iCodehTab); + iCodehTab = newHashTable (iCodeKey); + hashiCodeKeys (ebbs, count); + /* compute the control flow */ computeControlFlow (ebbs, count, 0); @@ -865,6 +1218,8 @@ eBBlockFromiCode (iCode * ic) if (options.dump_raw) dumpEbbsToFileExt (DUMP_RAW1, ebbs, count); + optimizeCastCast (ebbs, saveCount); + /* do common subexpression elimination for each block */ change = cseAllBlocks (ebbs, saveCount, FALSE); @@ -942,7 +1297,8 @@ eBBlockFromiCode (iCode * ic) bp; bp=setNextItem(ebbs[saveCount-1]->predList)) { if (bp->ech->op != RETURN) { - werror (W_VOID_FUNC, currFunc->name); + werrorfl (bp->ech->filename, bp->ech->lineno, + W_VOID_FUNC, currFunc->name); } } } @@ -974,7 +1330,7 @@ eBBlockFromiCode (iCode * ic) port->assignRegisters (ebbs, count); /* throw away blocks */ - setToNull ((void **) &graphEdges); + setToNull ((void *) &graphEdges); ebbs = NULL; return NULL;