ref: b04e71ed34cbbd9cb15f79cd20ba787438e6bcfb
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 "extern/err.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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "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(1, "Section \"%s\" defined as %s and %s", section->name,
sectionModNames[section->modifier], sectionModNames[other->modifier]);
else if (section->modifier == SECTION_NORMAL)
errx(1, "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(1, "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(1, "Sanity checks failed");
}