ref: 3741bd46171a143c5549422e8f55a2933b59eb97
dir: /src/asm/section.c/
#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "asm/fstack.h"
#include "asm/main.h"
#include "asm/output.h"
#include "asm/rpn.h"
#include "asm/section.h"
#include "asm/symbol.h"
#include "asm/warning.h"
#include "extern/err.h"
#include "platform.h" // strdup
uint8_t fillByte;
struct SectionStackEntry {
struct Section *section;
char const *scope; /* Section's symbol scope */
uint32_t offset;
struct SectionStackEntry *next;
};
struct SectionStackEntry *sectionStack;
uint32_t curOffset; /* Offset into the current section (see sect_GetSymbolOffset) */
static struct Section *currentLoadSection = NULL;
int32_t loadOffset; /* Offset into the LOAD section's parent (see sect_GetOutputOffset) */
struct UnionStackEntry {
uint32_t start;
uint32_t size;
struct UnionStackEntry *next;
} *unionStack = NULL;
/*
* A quick check to see if we have an initialized section
*/
static inline void checksection(void)
{
if (pCurrentSection == NULL)
fatalerror("Code generation before SECTION directive\n");
}
/*
* A quick check to see if we have an initialized section that can contain
* this much initialized data
*/
static inline void checkcodesection(void)
{
checksection();
if (!sect_HasData(pCurrentSection->type))
fatalerror("Section '%s' cannot contain code or data (not ROM0 or ROMX)\n",
pCurrentSection->name);
}
static inline void checkSectionSize(struct Section const *sect, uint32_t size)
{
uint32_t maxSize = maxsize[sect->type];
if (size > maxSize)
fatalerror("Section '%s' grew too big (max size = 0x%" PRIX32
" bytes, reached 0x%" PRIX32 ").\n", sect->name, maxSize, size);
}
/*
* Check if the section has grown too much.
*/
static inline void reserveSpace(uint32_t delta_size)
{
/*
* This check is here to trap broken code that generates sections that
* are too big and to prevent the assembler from generating huge object
* files or trying to allocate too much memory.
* A check at the linking stage is still necessary.
*/
checkSectionSize(pCurrentSection, curOffset + loadOffset + delta_size);
if (currentLoadSection)
checkSectionSize(currentLoadSection, curOffset + delta_size);
}
struct Section *out_FindSectionByName(const char *name)
{
for (struct Section *sect = pSectionList; sect; sect = sect->next) {
if (strcmp(name, sect->name) == 0)
return sect;
}
return NULL;
}
#define mask(align) ((1U << (align)) - 1)
#define fail(...) \
do { \
error(__VA_ARGS__); \
nbSectErrors++; \
} while (0)
static unsigned int mergeSectUnion(struct Section *sect, enum SectionType type, uint32_t org,
uint8_t alignment, uint16_t alignOffset)
{
assert(alignment < 16); // Should be ensured by the caller
unsigned int nbSectErrors = 0;
/*
* Unionized sections only need "compatible" constraints, and they end up with the strictest
* combination of both.
*/
if (sect_HasData(type))
fail("Cannot declare ROM sections as UNION\n");
if (org != (uint32_t)-1) {
/* If both are fixed, they must be the same */
if (sect->org != (uint32_t)-1 && sect->org != org)
fail("Section already declared as fixed at different address $%04"
PRIx32 "\n", sect->org);
else if (sect->align != 0 && (mask(sect->align) & (org - sect->alignOfs)))
fail("Section already declared as aligned to %u bytes (offset %"
PRIu16 ")\n", 1U << sect->align, sect->alignOfs);
else
/* Otherwise, just override */
sect->org = org;
} else if (alignment != 0) {
/* Make sure any fixed address given is compatible */
if (sect->org != (uint32_t)-1) {
if ((sect->org - alignOffset) & mask(alignment))
fail("Section already declared as fixed at incompatible address $%04"
PRIx32 "\n", sect->org);
/* Check if alignment offsets are compatible */
} else if ((alignOffset & mask(sect->align))
!= (sect->alignOfs & mask(alignment))) {
fail("Section already declared with incompatible %" PRIu8
"-byte alignment (offset %" PRIu16 ")\n",
sect->align, sect->alignOfs);
} else if (alignment > sect->align) {
// If the section is not fixed, its alignment is the largest of both
sect->align = alignment;
sect->alignOfs = alignOffset;
}
}
return nbSectErrors;
}
static unsigned int mergeFragments(struct Section *sect, enum SectionType type, uint32_t org,
uint8_t alignment, uint16_t alignOffset)
{
(void)type;
assert(alignment < 16); // Should be ensured by the caller
unsigned int nbSectErrors = 0;
/*
* Fragments only need "compatible" constraints, and they end up with the strictest
* combination of both.
* The merging is however performed at the *end* of the original section!
*/
if (org != (uint32_t)-1) {
uint16_t curOrg = org - sect->size;
/* If both are fixed, they must be the same */
if (sect->org != (uint32_t)-1 && sect->org != curOrg)
fail("Section already declared as fixed at incompatible address $%04"
PRIx32 " (cur addr = %04" PRIx32 ")\n",
sect->org, sect->org + sect->size);
else if (sect->align != 0 && (mask(sect->align) & (curOrg - sect->alignOfs)))
fail("Section already declared as aligned to %u bytes (offset %"
PRIu16 ")\n", 1U << sect->align, sect->alignOfs);
else
/* Otherwise, just override */
sect->org = curOrg;
} else if (alignment != 0) {
int32_t curOfs = (alignOffset - sect->size) % (1U << alignment);
if (curOfs < 0)
curOfs += 1U << alignment;
/* Make sure any fixed address given is compatible */
if (sect->org != (uint32_t)-1) {
if ((sect->org - curOfs) & mask(alignment))
fail("Section already declared as fixed at incompatible address $%04"
PRIx32 "\n", sect->org);
/* Check if alignment offsets are compatible */
} else if ((curOfs & mask(sect->align)) != (sect->alignOfs & mask(alignment))) {
fail("Section already declared with incompatible %" PRIu8
"-byte alignment (offset %" PRIu16 ")\n",
sect->align, sect->alignOfs);
} else if (alignment > sect->align) {
// If the section is not fixed, its alignment is the largest of both
sect->align = alignment;
sect->alignOfs = curOfs;
}
}
return nbSectErrors;
}
static void mergeSections(struct Section *sect, enum SectionType type, uint32_t org, uint32_t bank,
uint8_t alignment, uint16_t alignOffset, enum SectionModifier mod)
{
unsigned int nbSectErrors = 0;
if (type != sect->type)
fail("Section already exists but with type %s\n", typeNames[sect->type]);
if (sect->modifier != mod) {
fail("Section already declared as %s section\n", sectionModNames[sect->modifier]);
} else {
switch (mod) {
case SECTION_UNION:
case SECTION_FRAGMENT:
nbSectErrors += (mod == SECTION_UNION ? mergeSectUnion : mergeFragments)
(sect, type, org, alignment, alignOffset);
// Common checks
/* If the section's bank is unspecified, override it */
if (sect->bank == (uint32_t)-1)
sect->bank = bank;
/* If both specify a bank, it must be the same one */
else if (bank != (uint32_t)-1 && sect->bank != bank)
fail("Section already declared with different bank %" PRIu32 "\n",
sect->bank);
break;
case SECTION_NORMAL:
fail("Section already defined previously at ");
fstk_Dump(sect->src, sect->fileLine);
putc('\n', stderr);
break;
}
}
if (nbSectErrors)
fatalerror("Cannot create section \"%s\" (%u error%s)\n",
sect->name, nbSectErrors, nbSectErrors == 1 ? "" : "s");
}
#undef fail
/*
* Create a new section, not yet in the list.
*/
static struct Section *createSection(char const *name, enum SectionType type,
uint32_t org, uint32_t bank, uint8_t alignment,
uint16_t alignOffset, enum SectionModifier mod)
{
struct Section *sect = malloc(sizeof(*sect));
if (sect == NULL)
fatalerror("Not enough memory for section: %s\n", strerror(errno));
sect->name = strdup(name);
if (sect->name == NULL)
fatalerror("Not enough memory for section name: %s\n", strerror(errno));
sect->type = type;
sect->modifier = mod;
sect->src = fstk_GetFileStack();
sect->fileLine = lexer_GetLineNo();
sect->size = 0;
sect->org = org;
sect->bank = bank;
sect->align = alignment;
sect->alignOfs = alignOffset;
sect->next = NULL;
sect->patches = NULL;
/* It is only needed to allocate memory for ROM sections. */
if (sect_HasData(type)) {
sect->data = malloc(maxsize[type]);
if (sect->data == NULL)
fatalerror("Not enough memory for section: %s\n", strerror(errno));
} else {
sect->data = NULL;
}
return sect;
}
/*
* Find a section by name and type. If it doesn't exist, create it.
*/
static struct Section *getSection(char const *name, enum SectionType type, uint32_t org,
struct SectionSpec const *attrs, enum SectionModifier mod)
{
uint32_t bank = attrs->bank;
uint8_t alignment = attrs->alignment;
uint16_t alignOffset = attrs->alignOfs;
// First, validate parameters, and normalize them if applicable
if (bank != (uint32_t)-1) {
if (type != SECTTYPE_ROMX && type != SECTTYPE_VRAM
&& type != SECTTYPE_SRAM && type != SECTTYPE_WRAMX)
error("BANK only allowed for ROMX, WRAMX, SRAM, or VRAM sections\n");
else if (bank < bankranges[type][0]
|| bank > bankranges[type][1])
error("%s bank value $%04" PRIx32 " out of range ($%04" PRIx32 " to $%04"
PRIx32 ")\n", typeNames[type], bank,
bankranges[type][0], bankranges[type][1]);
} else if (nbbanks(type) == 1) {
// If the section type only has a single bank, implicitly force it
bank = bankranges[type][0];
}
if (alignOffset >= 1 << alignment) {
error("Alignment offset (%" PRIu16 ") must be smaller than alignment size (%u)\n",
alignOffset, 1U << alignment);
alignOffset = 0;
}
if (org != (uint32_t)-1) {
if (org < startaddr[type] || org > endaddr(type))
error("Section \"%s\"'s fixed address %#" PRIx32
" is outside of range [%#" PRIx16 "; %#" PRIx16 "]\n",
name, org, startaddr[type], endaddr(type));
}
if (alignment != 0) {
if (alignment > 16) {
error("Alignment must be between 0 and 16, not %u\n", alignment);
alignment = 16;
}
/* It doesn't make sense to have both alignment and org set */
uint32_t mask = mask(alignment);
if (org != (uint32_t)-1) {
if ((org - alignOffset) & mask)
error("Section \"%s\"'s fixed address doesn't match its alignment\n",
name);
alignment = 0; /* Ignore it if it's satisfied */
} else if (startaddr[type] & mask) {
error("Section \"%s\"'s alignment cannot be attained in %s\n",
name, typeNames[type]);
} else if (alignment == 16) {
// Treat an alignment of 16 as being fixed at address 0
alignment = 0;
org = 0;
// The address is known to be valid, since the alignment is
}
}
// Check if another section exists with the same name; merge if yes, otherwise create one
struct Section *sect = out_FindSectionByName(name);
if (sect) {
mergeSections(sect, type, org, bank, alignment, alignOffset, mod);
} else {
sect = createSection(name, type, org, bank, alignment, alignOffset, mod);
// Add the new section to the list (order doesn't matter)
sect->next = pSectionList;
pSectionList = sect;
}
return sect;
}
/*
* Set the current section
*/
static void changeSection(void)
{
if (unionStack)
fatalerror("Cannot change the section within a UNION\n");
sym_SetCurrentSymbolScope(NULL);
}
/*
* Set the current section by name and type
*/
void out_NewSection(char const *name, uint32_t type, uint32_t org,
struct SectionSpec const *attribs, enum SectionModifier mod)
{
if (currentLoadSection)
fatalerror("Cannot change the section within a `LOAD` block\n");
for (struct SectionStackEntry *stack = sectionStack; stack; stack = stack->next) {
if (stack->section && !strcmp(name, stack->section->name))
fatalerror("Section '%s' is already on the stack\n", name);
}
struct Section *sect = getSection(name, type, org, attribs, mod);
changeSection();
curOffset = mod == SECTION_UNION ? 0 : sect->size;
pCurrentSection = sect;
}
/*
* Set the current section by name and type
*/
void out_SetLoadSection(char const *name, uint32_t type, uint32_t org,
struct SectionSpec const *attribs,
enum SectionModifier mod)
{
checkcodesection();
if (currentLoadSection)
fatalerror("`LOAD` blocks cannot be nested\n");
if (sect_HasData(type))
error("`LOAD` blocks cannot create a ROM section\n");
struct Section *sect = getSection(name, type, org, attribs, mod);
changeSection();
loadOffset = curOffset - (mod == SECTION_UNION ? 0 : sect->size);
curOffset -= loadOffset;
currentLoadSection = sect;
}
void out_EndLoadSection(void)
{
if (!currentLoadSection)
error("Found `ENDL` outside of a `LOAD` block\n");
changeSection();
curOffset += loadOffset;
loadOffset = 0;
currentLoadSection = NULL;
}
struct Section *sect_GetSymbolSection(void)
{
return currentLoadSection ? currentLoadSection : pCurrentSection;
}
/*
* The offset into the section above
*/
uint32_t sect_GetSymbolOffset(void)
{
return curOffset;
}
uint32_t sect_GetOutputOffset(void)
{
return curOffset + loadOffset;
}
void sect_AlignPC(uint8_t alignment, uint16_t offset)
{
checksection();
struct Section *sect = sect_GetSymbolSection();
uint16_t alignSize = 1 << alignment; // Size of an aligned "block"
if (sect->org != (uint32_t)-1) {
if ((sym_GetPCValue() - offset) % alignSize)
error("Section's fixed address fails required alignment (PC = $%04" PRIx32
")\n", sym_GetPCValue());
} else if (sect->align != 0) {
if ((((sect->alignOfs + curOffset) % (1 << sect->align)) - offset) % alignSize) {
error("Section's alignment fails required alignment (offset from section start = $%04"
PRIx32 ")\n", curOffset);
} else if (alignment > sect->align) {
sect->align = alignment;
sect->alignOfs = (offset - curOffset) % alignSize;
}
} else {
sect->align = alignment;
// We need `(sect->alignOfs + curOffset) % alignSize == offset
sect->alignOfs = (offset - curOffset) % alignSize;
}
}
static inline void growSection(uint32_t growth)
{
curOffset += growth;
if (curOffset + loadOffset > pCurrentSection->size)
pCurrentSection->size = curOffset + loadOffset;
if (currentLoadSection && curOffset > currentLoadSection->size)
currentLoadSection->size = curOffset;
}
static inline void writebyte(uint8_t byte)
{
pCurrentSection->data[sect_GetOutputOffset()] = byte;
growSection(1);
}
static inline void writeword(uint16_t b)
{
writebyte(b & 0xFF);
writebyte(b >> 8);
}
static inline void writelong(uint32_t b)
{
writebyte(b & 0xFF);
writebyte(b >> 8);
writebyte(b >> 16);
writebyte(b >> 24);
}
static inline void createPatch(enum PatchType type, struct Expression const *expr,
uint32_t pcShift)
{
out_CreatePatch(type, expr, sect_GetOutputOffset(), pcShift);
}
void sect_StartUnion(void)
{
if (!pCurrentSection)
fatalerror("UNIONs must be inside a SECTION\n");
if (sect_HasData(pCurrentSection->type))
fatalerror("Cannot use UNION inside of ROM0 or ROMX sections\n");
struct UnionStackEntry *entry = malloc(sizeof(*entry));
if (!entry)
fatalerror("Failed to allocate new union stack entry: %s\n", strerror(errno));
entry->start = curOffset;
entry->size = 0;
entry->next = unionStack;
unionStack = entry;
}
static void endUnionMember(void)
{
uint32_t memberSize = curOffset - unionStack->start;
if (memberSize > unionStack->size)
unionStack->size = memberSize;
curOffset = unionStack->start;
}
void sect_NextUnionMember(void)
{
if (!unionStack)
fatalerror("Found NEXTU outside of a UNION construct\n");
endUnionMember();
}
void sect_EndUnion(void)
{
if (!unionStack)
fatalerror("Found ENDU outside of a UNION construct\n");
endUnionMember();
curOffset += unionStack->size;
struct UnionStackEntry *next = unionStack->next;
free(unionStack);
unionStack = next;
}
void sect_CheckUnionClosed(void)
{
if (unionStack)
error("Unterminated UNION construct!\n");
}
/*
* Output an absolute byte
*/
void out_AbsByte(uint8_t b)
{
checkcodesection();
reserveSpace(1);
writebyte(b);
}
void out_AbsByteGroup(uint8_t const *s, int32_t length)
{
checkcodesection();
reserveSpace(length);
while (length--)
writebyte(*s++);
}
void out_AbsWordGroup(uint8_t const *s, int32_t length)
{
checkcodesection();
reserveSpace(length * 2);
while (length--)
writeword(*s++);
}
void out_AbsLongGroup(uint8_t const *s, int32_t length)
{
checkcodesection();
reserveSpace(length * 4);
while (length--)
writelong(*s++);
}
/*
* Skip this many bytes
*/
void out_Skip(int32_t skip, bool ds)
{
checksection();
reserveSpace(skip);
if (!ds && sect_HasData(pCurrentSection->type))
warning(WARNING_EMPTY_DATA_DIRECTIVE, "%s directive without data in ROM\n",
(skip == 4) ? "DL" : (skip == 2) ? "DW" : "DB");
if (!sect_HasData(pCurrentSection->type)) {
growSection(skip);
} else {
checkcodesection();
while (skip--)
writebyte(fillByte);
}
}
/*
* Output a NULL terminated string (excluding the NULL-character)
*/
void out_String(char const *s)
{
checkcodesection();
reserveSpace(strlen(s));
while (*s)
writebyte(*s++);
}
/*
* Output a relocatable byte. Checking will be done to see if it
* is an absolute value in disguise.
*/
void out_RelByte(struct Expression *expr, uint32_t pcShift)
{
checkcodesection();
reserveSpace(1);
if (!rpn_isKnown(expr)) {
createPatch(PATCHTYPE_BYTE, expr, pcShift);
writebyte(0);
} else {
writebyte(expr->nVal);
}
rpn_Free(expr);
}
/*
* Output several copies of a relocatable byte. Checking will be done to see if
* it is an absolute value in disguise.
*/
void out_RelBytes(uint32_t n, struct Expression *exprs, size_t size)
{
checkcodesection();
reserveSpace(n);
for (uint32_t i = 0; i < n; i++) {
struct Expression *expr = &exprs[i % size];
if (!rpn_isKnown(expr)) {
createPatch(PATCHTYPE_BYTE, expr, i);
writebyte(0);
} else {
writebyte(expr->nVal);
}
}
for (size_t i = 0; i < size; i++)
rpn_Free(&exprs[i]);
}
/*
* Output a relocatable word. Checking will be done to see if
* it's an absolute value in disguise.
*/
void out_RelWord(struct Expression *expr, uint32_t pcShift)
{
checkcodesection();
reserveSpace(2);
if (!rpn_isKnown(expr)) {
createPatch(PATCHTYPE_WORD, expr, pcShift);
writeword(0);
} else {
writeword(expr->nVal);
}
rpn_Free(expr);
}
/*
* Output a relocatable longword. Checking will be done to see if
* is an absolute value in disguise.
*/
void out_RelLong(struct Expression *expr, uint32_t pcShift)
{
checkcodesection();
reserveSpace(2);
if (!rpn_isKnown(expr)) {
createPatch(PATCHTYPE_LONG, expr, pcShift);
writelong(0);
} else {
writelong(expr->nVal);
}
rpn_Free(expr);
}
/*
* Output a PC-relative relocatable byte. Checking will be done to see if it
* is an absolute value in disguise.
*/
void out_PCRelByte(struct Expression *expr, uint32_t pcShift)
{
checkcodesection();
reserveSpace(1);
struct Symbol const *pc = sym_GetPC();
if (!rpn_IsDiffConstant(expr, pc)) {
createPatch(PATCHTYPE_JR, expr, pcShift);
writebyte(0);
} else {
struct Symbol const *sym = rpn_SymbolOf(expr);
/* The offset wraps (jump from ROM to HRAM, for example) */
int16_t offset;
/* Offset is relative to the byte *after* the operand */
if (sym == pc)
offset = -2; /* PC as operand to `jr` is lower than reference PC by 2 */
else
offset = sym_GetValue(sym) - (sym_GetValue(pc) + 1);
if (offset < -128 || offset > 127) {
error("jr target out of reach (expected -129 < %" PRId16 " < 128)\n",
offset);
writebyte(0);
} else {
writebyte(offset);
}
}
rpn_Free(expr);
}
/*
* Output a binary file
*/
void out_BinaryFile(char const *s, int32_t startPos)
{
if (startPos < 0) {
error("Start position cannot be negative (%" PRId32 ")\n", startPos);
startPos = 0;
}
char *fullPath = NULL;
size_t size = 0;
FILE *f = NULL;
if (fstk_FindFile(s, &fullPath, &size))
f = fopen(fullPath, "rb");
free(fullPath);
if (!f) {
if (oGeneratedMissingIncludes) {
if (verbose)
printf("Aborting (-MG) on INCBIN file '%s' (%s)\n", s, strerror(errno));
oFailedOnMissingInclude = true;
return;
}
error("Error opening INCBIN file '%s': %s\n", s, strerror(errno));
return;
}
int32_t fsize = -1;
int byte;
checkcodesection();
if (fseek(f, 0, SEEK_END) != -1) {
fsize = ftell(f);
if (startPos > fsize) {
error("Specified start position is greater than length of file\n");
fclose(f);
return;
}
fseek(f, startPos, SEEK_SET);
reserveSpace(fsize - startPos);
} else {
if (errno != ESPIPE)
error("Error determining size of INCBIN file '%s': %s\n",
s, strerror(errno));
/* The file isn't seekable, so we'll just skip bytes */
while (startPos--)
(void)fgetc(f);
}
while ((byte = fgetc(f)) != EOF) {
if (fsize == -1)
growSection(1);
writebyte(byte);
}
if (ferror(f))
error("Error reading INCBIN file '%s': %s\n", s, strerror(errno));
fclose(f);
}
void out_BinaryFileSlice(char const *s, int32_t start_pos, int32_t length)
{
if (start_pos < 0) {
error("Start position cannot be negative (%" PRId32 ")\n", start_pos);
start_pos = 0;
}
if (length < 0) {
error("Number of bytes to read cannot be negative (%" PRId32 ")\n", length);
length = 0;
}
if (length == 0) /* Don't even bother with 0-byte slices */
return;
char *fullPath = NULL;
size_t size = 0;
FILE *f = NULL;
if (fstk_FindFile(s, &fullPath, &size))
f = fopen(fullPath, "rb");
if (!f) {
free(fullPath);
if (oGeneratedMissingIncludes) {
if (verbose)
printf("Aborting (-MG) on INCBIN file '%s' (%s)\n", s, strerror(errno));
oFailedOnMissingInclude = true;
return;
}
error("Error opening INCBIN file '%s': %s\n", s, strerror(errno));
return;
}
checkcodesection();
reserveSpace(length);
int32_t fsize;
if (fseek(f, 0, SEEK_END) != -1) {
fsize = ftell(f);
if (start_pos > fsize) {
error("Specified start position is greater than length of file\n");
return;
}
if ((start_pos + length) > fsize) {
error("Specified range in INCBIN is out of bounds (%" PRIu32 " + %" PRIu32
" > %" PRIu32 ")\n", start_pos, length, fsize);
return;
}
fseek(f, start_pos, SEEK_SET);
} else {
if (errno != ESPIPE)
error("Error determining size of INCBIN file '%s': %s\n",
s, strerror(errno));
/* The file isn't seekable, so we'll just skip bytes */
while (start_pos--)
(void)fgetc(f);
}
int32_t todo = length;
while (todo--) {
int byte = fgetc(f);
if (byte != EOF) {
writebyte(byte);
} else if (ferror(f)) {
error("Error reading INCBIN file '%s': %s\n", s, strerror(errno));
} else {
error("Premature end of file (%" PRId32 " bytes left to read)\n",
todo + 1);
}
}
fclose(f);
free(fullPath);
}
/*
* Section stack routines
*/
void out_PushSection(void)
{
struct SectionStackEntry *sect = malloc(sizeof(*sect));
if (sect == NULL)
fatalerror("No memory for section stack: %s\n", strerror(errno));
sect->section = pCurrentSection;
sect->scope = sym_GetCurrentSymbolScope();
sect->offset = curOffset;
sect->next = sectionStack;
sectionStack = sect;
/* TODO: maybe set current section to NULL? */
}
void out_PopSection(void)
{
if (!sectionStack)
fatalerror("No entries in the section stack\n");
if (currentLoadSection)
fatalerror("Cannot change the section within a `LOAD` block!\n");
struct SectionStackEntry *sect;
sect = sectionStack;
changeSection();
pCurrentSection = sect->section;
sym_SetCurrentSymbolScope(sect->scope);
curOffset = sect->offset;
sectionStack = sect->next;
free(sect);
}