ref: d9b1402ef872edf36884670dbff30fdd2467efda
dir: /src/link/section.c/
/* * This file is part of RGBDS. * * Copyright (c) 2019, Eldred Habert and RGBDS contributors. * * SPDX-License-Identifier: MIT */ #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" 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, typeNames[target->type], typeNames[other->type]); 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); target->size += other->size; other->offset = target->size - other->size; if (sect_HasData(target->type)) { /* 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 + target->size - other->size, other->data, other->size); /* Adjust patches' PC offsets */ for (uint32_t patchID = 0; patchID < other->nbPatches; patchID++) other->patches[patchID].pcOffset += other->offset; } 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, typeNames[section->type]); } 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 bool sanityChecksFailed; static void doSanityChecks(struct Section *section, void *ptr) { (void)ptr; #define fail(...) do { \ warnx(__VA_ARGS__); \ sanityChecksFailed = true; \ } while (0) /* Sanity check the section's type */ if (section->type < 0 || section->type >= SECTTYPE_INVALID) fail("Section \"%s\" has an invalid type.", section->name); if (is32kMode && section->type == SECTTYPE_ROMX) { if (section->isBankFixed && section->bank != 1) fail("%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) fail("%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) fail("%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 & startaddr[section->type])) fail("%s: %s sections cannot be aligned to $%04x bytes", section->name, typeNames[section->type], section->alignMask + 1); uint32_t minbank = bankranges[section->type][0], maxbank = bankranges[section->type][1]; if (section->isBankFixed && section->bank < minbank && section->bank > maxbank) fail(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 > maxsize[section->type]) fail("Section \"%s\" is bigger than the max size for that type: %#" PRIx16 " > %#" PRIx16, section->name, section->size, maxsize[section->type]); /* 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) fail("Section \"%s\"'s fixed address doesn't match its alignment", section->name); section->isAlignFixed = false; } /* Ensure the target address is valid */ if (section->org < startaddr[section->type] || section->org > endaddr(section->type)) fail("Section \"%s\"'s fixed address %#" PRIx16 " is outside of range [%#" PRIx16 "; %#" PRIx16 "]", section->name, section->org, startaddr[section->type], endaddr(section->type)); if (section->org + section->size > endaddr(section->type) + 1) fail("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); if (sanityChecksFailed) errx("Sanity checks failed"); }