ref: 599ce757a1f644aba35d692cec68202944f7163f
dir: /src/link/section.c/
/* * This file is part of RGBDS. * * Copyright (c) 2019, Eldred Habert and RGBDS contributors. * * SPDX-License-Identifier: MIT */ #include <assert.h> #include <inttypes.h> #include <stdbool.h> #include <stdlib.h> #include <string.h> #include "link/main.h" #include "link/section.h" #include "error.h" #include "hashmap.h" #include "linkdefs.h" HashMap sections; struct ForEachArg { void (*callback)(struct Section *section, void *arg); void *arg; }; static void forEach(void *section, void *arg) { struct ForEachArg *callbackArg = (struct ForEachArg *)arg; callbackArg->callback((struct Section *)section, callbackArg->arg); } void sect_ForEach(void (*callback)(struct Section *, void *), void *arg) { struct ForEachArg callbackArg = { .callback = callback, .arg = arg}; hash_ForEach(sections, forEach, &callbackArg); } static void checkSectUnionCompat(struct Section *target, struct Section *other) { if (other->isAddressFixed) { if (target->isAddressFixed) { if (target->org != other->org) errx("Section \"%s\" is defined with conflicting addresses $%04" PRIx16 " and $%04" PRIx16, other->name, target->org, other->org); } else if (target->isAlignFixed) { if ((other->org - target->alignOfs) & target->alignMask) errx("Section \"%s\" is defined with conflicting %d-byte alignment (offset %" PRIu16 ") and address $%04" PRIx16, other->name, target->alignMask + 1, target->alignOfs, other->org); } target->isAddressFixed = true; target->org = other->org; } else if (other->isAlignFixed) { if (target->isAddressFixed) { if ((target->org - other->alignOfs) & other->alignMask) errx("Section \"%s\" is defined with conflicting address $%04" PRIx16 " and %d-byte alignment (offset %" PRIu16 ")", other->name, target->org, other->alignMask + 1, other->alignOfs); } else if (target->isAlignFixed && (other->alignMask & target->alignOfs) != (target->alignMask & other->alignOfs)) { errx("Section \"%s\" is defined with conflicting %d-byte alignment (offset %" PRIu16 ") and %d-byte alignment (offset %" PRIu16 ")", other->name, target->alignMask + 1, target->alignOfs, other->alignMask + 1, other->alignOfs); } else if (!target->isAlignFixed || (other->alignMask > target->alignMask)) { target->isAlignFixed = true; target->alignMask = other->alignMask; } } } static void checkFragmentCompat(struct Section *target, struct Section *other) { if (other->isAddressFixed) { uint16_t org = other->org - target->size; if (target->isAddressFixed) { if (target->org != org) errx("Section \"%s\" is defined with conflicting addresses $%04" PRIx16 " and $%04" PRIx16, other->name, target->org, other->org); } else if (target->isAlignFixed) { if ((org - target->alignOfs) & target->alignMask) errx("Section \"%s\" is defined with conflicting %d-byte alignment (offset %" PRIu16 ") and address $%04" PRIx16, other->name, target->alignMask + 1, target->alignOfs, other->org); } target->isAddressFixed = true; target->org = org; } else if (other->isAlignFixed) { int32_t ofs = (other->alignOfs - target->size) % (other->alignMask + 1); if (ofs < 0) ofs += other->alignMask + 1; if (target->isAddressFixed) { if ((target->org - ofs) & other->alignMask) errx("Section \"%s\" is defined with conflicting address $%04" PRIx16 " and %d-byte alignment (offset %" PRIu16 ")", other->name, target->org, other->alignMask + 1, other->alignOfs); } else if (target->isAlignFixed && (other->alignMask & target->alignOfs) != (target->alignMask & ofs)) { errx("Section \"%s\" is defined with conflicting %d-byte alignment (offset %" PRIu16 ") and %d-byte alignment (offset %" PRIu16 ")", other->name, target->alignMask + 1, target->alignOfs, other->alignMask + 1, other->alignOfs); } else if (!target->isAlignFixed || (other->alignMask > target->alignMask)) { target->isAlignFixed = true; target->alignMask = other->alignMask; target->alignOfs = ofs; } } } static void mergeSections(struct Section *target, struct Section *other, enum SectionModifier mod) { // Common checks if (target->type != other->type) errx("Section \"%s\" is defined with conflicting types %s and %s", other->name, sectionTypeInfo[target->type].name, sectionTypeInfo[other->type].name); if (other->isBankFixed) { if (!target->isBankFixed) { target->isBankFixed = true; target->bank = other->bank; } else if (target->bank != other->bank) { errx("Section \"%s\" is defined with conflicting banks %" PRIu32 " and %" PRIu32, other->name, target->bank, other->bank); } } switch (mod) { case SECTION_UNION: checkSectUnionCompat(target, other); if (other->size > target->size) target->size = other->size; break; case SECTION_FRAGMENT: checkFragmentCompat(target, other); // Append `other` to `target` // Note that the order in which fragments are stored in the `nextu` list does not // really matter, only that offsets are properly computed other->offset = target->size; target->size += other->size; // Normally we'd check that `sect_HasData`, but SDCC areas may be `_INVALID` here // Note that if either fragment has data (= a non-NULL `data` pointer), then it's // assumed that both fragments "have data", and thus should either have a non-NULL // `data` pointer, or a size of 0. if (other->data) { if (target->data) { // Ensure we're not allocating 0 bytes target->data = realloc(target->data, sizeof(*target->data) * target->size + 1); if (!target->data) errx("Failed to concatenate \"%s\"'s fragments", target->name); memcpy(&target->data[other->offset], other->data, other->size); } else { assert(target->size == other->size); // It has been increased just above target->data = other->data; other->data = NULL; // Prevent a double free() } // Adjust patches' PC offsets for (uint32_t patchID = 0; patchID < other->nbPatches; patchID++) other->patches[patchID].pcOffset += other->offset; } else if (target->data) { assert(other->size == 0); } break; case SECTION_NORMAL: unreachable_(); } other->nextu = target->nextu; target->nextu = other; } void sect_AddSection(struct Section *section) { // Check if the section already exists struct Section *other = hash_GetElement(sections, section->name); if (other) { if (section->modifier != other->modifier) errx("Section \"%s\" defined as %s and %s", section->name, sectionModNames[section->modifier], sectionModNames[other->modifier]); else if (section->modifier == SECTION_NORMAL) errx("Section name \"%s\" is already in use", section->name); else mergeSections(other, section, section->modifier); } else if (section->modifier == SECTION_UNION && sect_HasData(section->type)) { errx("Section \"%s\" is of type %s, which cannot be unionized", section->name, sectionTypeInfo[section->type].name); } else { // If not, add it hash_AddElement(sections, section->name, section); } } struct Section *sect_GetSection(char const *name) { return (struct Section *)hash_GetElement(sections, name); } void sect_CleanupSections(void) { hash_EmptyMap(sections); } static void doSanityChecks(struct Section *section, void *ptr) { (void)ptr; // Sanity check the section's type if (section->type < 0 || section->type >= SECTTYPE_INVALID) { error(NULL, 0, "Section \"%s\" has an invalid type", section->name); return; } if (is32kMode && section->type == SECTTYPE_ROMX) { if (section->isBankFixed && section->bank != 1) error(NULL, 0, "%s: ROMX sections must be in bank 1 (if any) with option -t", section->name); else section->type = SECTTYPE_ROM0; } if (isWRA0Mode && section->type == SECTTYPE_WRAMX) { if (section->isBankFixed && section->bank != 1) error(NULL, 0, "%s: WRAMX sections must be in bank 1 with options -w or -d", section->name); else section->type = SECTTYPE_WRAMX; } if (isDmgMode && section->type == SECTTYPE_VRAM && section->bank == 1) error(NULL, 0, "%s: VRAM bank 1 can't be used with option -d", section->name); // Check if alignment is reasonable, this is important to avoid UB // An alignment of zero is equivalent to no alignment, basically if (section->isAlignFixed && section->alignMask == 0) section->isAlignFixed = false; // Too large an alignment may not be satisfiable if (section->isAlignFixed && (section->alignMask & sectionTypeInfo[section->type].startAddr)) error(NULL, 0, "%s: %s sections cannot be aligned to $%04x bytes", section->name, sectionTypeInfo[section->type].name, section->alignMask + 1); uint32_t minbank = sectionTypeInfo[section->type].firstBank, maxbank = sectionTypeInfo[section->type].lastBank; if (section->isBankFixed && section->bank < minbank && section->bank > maxbank) error(NULL, 0, minbank == maxbank ? "Cannot place section \"%s\" in bank %" PRIu32 ", it must be %" PRIu32 : "Cannot place section \"%s\" in bank %" PRIu32 ", it must be between %" PRIu32 " and %" PRIu32, section->name, section->bank, minbank, maxbank); // Check if section has a chance to be placed if (section->size > sectionTypeInfo[section->type].size) error(NULL, 0, "Section \"%s\" is bigger than the max size for that type: %#" PRIx16 " > %#" PRIx16, section->name, section->size, sectionTypeInfo[section->type].size); // Translate loose constraints to strong ones when they're equivalent if (minbank == maxbank) { section->bank = minbank; section->isBankFixed = true; } if (section->isAddressFixed) { // It doesn't make sense to have both org and alignment set if (section->isAlignFixed) { if ((section->org & section->alignMask) != section->alignOfs) error(NULL, 0, "Section \"%s\"'s fixed address doesn't match its alignment", section->name); section->isAlignFixed = false; } // Ensure the target address is valid if (section->org < sectionTypeInfo[section->type].startAddr || section->org > endaddr(section->type)) error(NULL, 0, "Section \"%s\"'s fixed address %#" PRIx16 " is outside of range [%#" PRIx16 "; %#" PRIx16 "]", section->name, section->org, sectionTypeInfo[section->type].startAddr, endaddr(section->type)); if (section->org + section->size > endaddr(section->type) + 1) error(NULL, 0, "Section \"%s\"'s end address %#x is greater than last address %#x", section->name, section->org + section->size, endaddr(section->type) + 1); } #undef fail } void sect_DoSanityChecks(void) { sect_ForEach(doSanityChecks, NULL); }