ref: 9687e6e1dd071ccceb427cc5d6ac03f2d313e79f
dir: /src/asm/rpn.c/
/* * This file is part of RGBDS. * * Copyright (c) 1997-2018, Carsten Sorensen and RGBDS contributors. * * SPDX-License-Identifier: MIT */ /* * Controls RPN expressions for objectfiles */ #include <assert.h> #include <stdint.h> #include <stdio.h> #include <string.h> #include "asm/asm.h" #include "asm/main.h" #include "asm/rpn.h" #include "asm/symbol.h" #include "asm/output.h" #include "asm/warning.h" #include "linkdefs.h" void mergetwoexpressions(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { assert(src1->tRPN != NULL && src2->tRPN != NULL); if (src1->nRPNLength + src2->nRPNLength > MAXRPNLEN) fatalerror("RPN expression is too large"); uint32_t len = src1->nRPNLength + src2->nRPNLength; expr->nVal = 0; expr->tRPN = src1->tRPN; if (src1->nRPNCapacity >= len) { expr->nRPNCapacity = src1->nRPNCapacity; } else { uint32_t cap1 = src1->nRPNCapacity; uint32_t cap2 = src2->nRPNCapacity; uint32_t cap = (cap1 > cap2) ? cap1 : cap2; if (len > cap) cap = (cap <= MAXRPNLEN / 2) ? cap * 2 : MAXRPNLEN; expr->nRPNCapacity = cap; expr->tRPN = realloc(expr->tRPN, expr->nRPNCapacity); if (expr->tRPN == NULL) fatalerror("No memory for RPN expression"); } memcpy(expr->tRPN + src1->nRPNLength, src2->tRPN, src2->nRPNLength); free(src2->tRPN); expr->nRPNLength = len; expr->nRPNPatchSize = src1->nRPNPatchSize + src2->nRPNPatchSize; expr->nRPNOut = 0; expr->isReloc = src1->isReloc || src2->isReloc; } /* * Add a byte to the RPN expression */ void pushbyte(struct Expression *expr, uint8_t b) { if (expr->nRPNLength == expr->nRPNCapacity) { if (expr->nRPNCapacity == 0) expr->nRPNCapacity = 256; else if (expr->nRPNCapacity == MAXRPNLEN) fatalerror("RPN expression is too large"); else if (expr->nRPNCapacity > MAXRPNLEN / 2) expr->nRPNCapacity = MAXRPNLEN; else expr->nRPNCapacity *= 2; expr->tRPN = realloc(expr->tRPN, expr->nRPNCapacity); if (expr->tRPN == NULL) fatalerror("No memory for RPN expression"); } expr->tRPN[expr->nRPNLength++] = b; } /* * Init the RPN expression */ void rpn_Init(struct Expression *expr) { expr->tRPN = NULL; expr->nRPNCapacity = 0; expr->nRPNLength = 0; expr->nRPNPatchSize = 0; expr->nRPNOut = 0; expr->isReloc = 0; } /* * Free the RPN expression */ void rpn_Free(struct Expression *expr) { free(expr->tRPN); rpn_Init(expr); } /* * Returns the next rpn byte in expression */ uint16_t rpn_PopByte(struct Expression *expr) { if (expr->nRPNOut == expr->nRPNLength) return 0xDEAD; return expr->tRPN[expr->nRPNOut++]; } /* * Determine if the current expression is relocatable */ uint32_t rpn_isReloc(const struct Expression *expr) { return expr->isReloc; } /* * Add symbols, constants and operators to expression */ void rpn_Number(struct Expression *expr, uint32_t i) { rpn_Init(expr); pushbyte(expr, RPN_CONST); pushbyte(expr, i); pushbyte(expr, i >> 8); pushbyte(expr, i >> 16); pushbyte(expr, i >> 24); expr->nVal = i; expr->nRPNPatchSize += 5; } void rpn_Symbol(struct Expression *expr, char *tzSym) { struct sSymbol *sym = sym_FindSymbol(tzSym); if (!sym || !sym_IsConstant(sym)) { rpn_Init(expr); sym_Ref(tzSym); expr->isReloc = 1; pushbyte(expr, RPN_SYM); while (*tzSym) pushbyte(expr, *tzSym++); pushbyte(expr, 0); expr->nRPNPatchSize += 5; } else { rpn_Number(expr, sym_GetConstantValue(tzSym)); } } void rpn_BankSelf(struct Expression *expr) { rpn_Init(expr); if (pCurrentSection->nBank == -1) /* * This is not really relocatable, but this makes the assembler * write this expression as a RPN patch to the object file. */ expr->isReloc = 1; else expr->nVal = pCurrentSection->nBank; pushbyte(expr, RPN_BANK_SELF); expr->nRPNPatchSize++; } void rpn_BankSymbol(struct Expression *expr, char *tzSym) { struct sSymbol const *sym = sym_FindSymbol(tzSym); /* The @ symbol is treated differently. */ if (sym == pPCSymbol) { rpn_BankSelf(expr); return; } if (sym && sym_IsConstant(sym)) { yyerror("BANK argument must be a relocatable identifier"); } else { rpn_Init(expr); sym_Ref(tzSym); pushbyte(expr, RPN_BANK_SYM); for (unsigned int i = 0; tzSym[i]; i++) pushbyte(expr, tzSym[i]); pushbyte(expr, 0); expr->nRPNPatchSize += 5; /* If the symbol didn't exist, `sym_Ref` created it */ struct sSymbol *pSymbol = sym_FindSymbol(tzSym); if (pSymbol->pSection && pSymbol->pSection->nBank != -1) /* Symbol's section is known and bank's fixed */ expr->nVal = pSymbol->pSection->nBank; else expr->isReloc = 1; } } void rpn_BankSection(struct Expression *expr, char *tzSectionName) { rpn_Init(expr); struct Section *pSection = out_FindSectionByName(tzSectionName); if (pSection && pSection->nBank != -1) expr->nVal = pSection->nBank; else /* * This is not really relocatable, but this makes the assembler * write this expression as a RPN patch to the object file. */ expr->isReloc = 1; pushbyte(expr, RPN_BANK_SECT); expr->nRPNPatchSize++; while (*tzSectionName) { pushbyte(expr, *tzSectionName++); expr->nRPNPatchSize++; } pushbyte(expr, 0); expr->nRPNPatchSize++; } void rpn_CheckHRAM(struct Expression *expr, const struct Expression *src) { *expr = *src; pushbyte(expr, RPN_HRAM); expr->nRPNPatchSize++; } void rpn_CheckRST(struct Expression *expr, const struct Expression *src) { *expr = *src; pushbyte(expr, RPN_RST); expr->nRPNPatchSize++; } void rpn_LOGNOT(struct Expression *expr, const struct Expression *src) { *expr = *src; expr->nVal = !expr->nVal; pushbyte(expr, RPN_LOGUNNOT); expr->nRPNPatchSize++; } void rpn_LOGOR(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal || src2->nVal); pushbyte(expr, RPN_LOGOR); expr->nRPNPatchSize++; } void rpn_LOGAND(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal && src2->nVal); pushbyte(expr, RPN_LOGAND); expr->nRPNPatchSize++; } void rpn_HIGH(struct Expression *expr, const struct Expression *src) { *expr = *src; expr->nVal = (expr->nVal >> 8) & 0xFF; pushbyte(expr, RPN_CONST); pushbyte(expr, 8); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, RPN_SHR); pushbyte(expr, RPN_CONST); pushbyte(expr, 0xFF); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, RPN_AND); expr->nRPNPatchSize += 12; } void rpn_LOW(struct Expression *expr, const struct Expression *src) { *expr = *src; expr->nVal = expr->nVal & 0xFF; pushbyte(expr, RPN_CONST); pushbyte(expr, 0xFF); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, 0); pushbyte(expr, RPN_AND); expr->nRPNPatchSize += 6; } void rpn_LOGEQU(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal == src2->nVal); pushbyte(expr, RPN_LOGEQ); expr->nRPNPatchSize++; } void rpn_LOGGT(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal > src2->nVal); pushbyte(expr, RPN_LOGGT); expr->nRPNPatchSize++; } void rpn_LOGLT(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal < src2->nVal); pushbyte(expr, RPN_LOGLT); expr->nRPNPatchSize++; } void rpn_LOGGE(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal >= src2->nVal); pushbyte(expr, RPN_LOGGE); expr->nRPNPatchSize++; } void rpn_LOGLE(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal <= src2->nVal); pushbyte(expr, RPN_LOGLE); expr->nRPNPatchSize++; } void rpn_LOGNE(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal != src2->nVal); pushbyte(expr, RPN_LOGNE); expr->nRPNPatchSize++; } void rpn_ADD(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = ((uint32_t)src1->nVal + (uint32_t)src2->nVal); pushbyte(expr, RPN_ADD); expr->nRPNPatchSize++; } void rpn_SUB(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = ((uint32_t)src1->nVal - (uint32_t)src2->nVal); pushbyte(expr, RPN_SUB); expr->nRPNPatchSize++; } void rpn_XOR(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal ^ src2->nVal); pushbyte(expr, RPN_XOR); expr->nRPNPatchSize++; } void rpn_OR(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal | src2->nVal); pushbyte(expr, RPN_OR); expr->nRPNPatchSize++; } void rpn_AND(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = (src1->nVal & src2->nVal); pushbyte(expr, RPN_AND); expr->nRPNPatchSize++; } static int32_t shift(int32_t shiftee, int32_t amount) { if (shiftee < 0) warning(WARNING_SHIFT, "Shifting negative value %d", shiftee); if (amount >= 0) { // Left shift if (amount >= 32) { warning(WARNING_SHIFT_AMOUNT, "Shifting left by large amount %d", amount); return 0; } else { /* * Use unsigned to force a bitwise shift * Casting back is OK because the types implement two's * complement behavior */ return (uint32_t)shiftee << amount; } } else { // Right shift amount = -amount; if (amount >= 32) { warning(WARNING_SHIFT_AMOUNT, "Shifting right by large amount %d", amount); return shiftee < 0 ? -1 : 0; } else if (shiftee >= 0) { return shiftee >> amount; } else { /* * The C standard leaves shifting right negative values * undefined, so use a left shift manually sign-extended */ return (uint32_t)shiftee >> amount | -((uint32_t)1 << (32 - amount)); } } } void rpn_SHL(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); if (!expr->isReloc) { if (src2->nVal < 0) warning(WARNING_SHIFT_AMOUNT, "Shifting left by negative value: %d", src2->nVal); expr->nVal = shift(src1->nVal, src2->nVal); } pushbyte(expr, RPN_SHL); expr->nRPNPatchSize++; } void rpn_SHR(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); if (!expr->isReloc) { if (src2->nVal < 0) warning(WARNING_SHIFT_AMOUNT, "Shifting right by negative value: %d", src2->nVal); expr->nVal = shift(src1->nVal, -src2->nVal); } pushbyte(expr, RPN_SHR); expr->nRPNPatchSize++; } void rpn_MUL(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); expr->nVal = ((uint32_t)src1->nVal * (uint32_t)src2->nVal); pushbyte(expr, RPN_MUL); expr->nRPNPatchSize++; } void rpn_DIV(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); if (!expr->isReloc) { if (src2->nVal == 0) fatalerror("Division by zero"); if (src1->nVal == INT32_MIN && src2->nVal == -1) { warning(WARNING_DIV, "Division of min value by -1"); expr->nVal = INT32_MIN; } else { expr->nVal = (src1->nVal / src2->nVal); } } pushbyte(expr, RPN_DIV); expr->nRPNPatchSize++; } void rpn_MOD(struct Expression *expr, const struct Expression *src1, const struct Expression *src2) { mergetwoexpressions(expr, src1, src2); if (!expr->isReloc) { if (src2->nVal == 0) fatalerror("Division by zero"); if (src1->nVal == INT32_MIN && src2->nVal == -1) expr->nVal = 0; else expr->nVal = (src1->nVal % src2->nVal); } pushbyte(expr, RPN_MOD); expr->nRPNPatchSize++; } void rpn_UNNEG(struct Expression *expr, const struct Expression *src) { *expr = *src; expr->nVal = -(uint32_t)expr->nVal; pushbyte(expr, RPN_UNSUB); expr->nRPNPatchSize++; } void rpn_UNNOT(struct Expression *expr, const struct Expression *src) { *expr = *src; expr->nVal = ~expr->nVal; pushbyte(expr, RPN_UNNOT); expr->nRPNPatchSize++; }