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Rewrite RGBLINK entirely

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The goal was to improve readability, but along the way a few things were
gained.
- Sorted sym and map files
- Infrastructure for supporting multiple .o versions
- Valgrind-proof, as far as my testing goes anyways
- Improved verbosity messages
- Added error checking
- Performance improvements, see end of commit message

The readability improvement was spurred while trying to make sense of the
old code while trying to implement features such as sorted sym and map
files.
I also did my best to remove hardcoded logic, such that modifications
should be doable; for example, "RAM loading" sections, which are linked
against a different location than the one they're stored at.

Some work remains to be done, see the "TODO:" and "FIXME:" comments.
Further, while regression tests pass, this new linker should be tested on
different codebases (ideally while instrumented with `make develop` and
under valgrind).
The few errors spotted in the man pages (alignment) need to be corrected.
Finally, documentation comments need to be written, I have written a lot of
them but not all.

This also provides a significant performance boost (benchmarked with a
51994-symbol project):

Current master RGBLINK:
2.02user 0.03system 0:02.06elapsed 99%CPU (0avgtext+0avgdata 84336maxresident)k
0inputs+11584outputs (0major+20729minor)pagefaults 0swaps

Rewritten RGBLINK:
0.19user 0.06system 0:00.63elapsed 40%CPU (0avgtext+0avgdata 32460maxresident)k
23784inputs+11576outputs (0major+7672minor)pagefaults 0swaps
This commit is contained in:
ISSOtm
2019-09-19 14:27:37 +02:00
parent 696feae32e
commit 0e24adcafd
39 changed files with 2507 additions and 2630 deletions
Download Patch File Download Diff File Expand all files Collapse all files

141
src/link/symbol.c
View File

@@ -1,137 +1,56 @@
/*
* This file is part of RGBDS.
*
* Copyright (c) 1997-2018, Carsten Sorensen and RGBDS contributors.
*
* SPDX-License-Identifier: MIT
*/
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "extern/err.h"
#include <stdbool.h>
#include "link/symbol.h"
#include "link/main.h"
#include "link/patch.h"
#include "link/mylink.h"
#include "extern/err.h"
#include "hashmap.h"
#include "types.h"
HashMap symbols;
#define HASHSIZE 73
struct ISymbol {
char *pzName;
int32_t nValue;
int32_t nBank; /* -1 = constant */
/* Object file where the symbol was defined. */
char tzObjFileName[_MAX_PATH + 1];
/* Source file where the symbol was defined. */
char tzFileName[_MAX_PATH + 1];
/* Line where the symbol was defined. */
uint32_t nFileLine;
struct ISymbol *pNext;
struct ForEachArg {
void (*callback)(struct Symbol *symbol, void *arg);
void *arg;
};
struct ISymbol *tHash[HASHSIZE];
int32_t calchash(char *s)
static void forEach(void *symbol, void *arg)
{
int32_t r = 0;
struct ForEachArg *callbackArg = (struct ForEachArg *)arg;
while (*s)
r += *s++;
return r % HASHSIZE;
callbackArg->callback((struct Symbol *)symbol, callbackArg->arg);
}
void sym_Init(void)
void sym_ForEach(void (*callback)(struct Symbol *, void *), void *arg)
{
int32_t i;
struct ForEachArg callbackArg = { .callback = callback, .arg = arg};
for (i = 0; i < HASHSIZE; i += 1)
tHash[i] = NULL;
hash_ForEach(symbols, forEach, &callbackArg);
}
int32_t sym_GetValue(struct sPatch *pPatch, char *tzName)
void sym_AddSymbol(struct Symbol *symbol)
{
if (strcmp(tzName, "@") == 0)
return nPC;
/* Check if the symbol already exists */
struct Symbol *other = hash_GetElement(symbols, symbol->name);
struct ISymbol **ppSym;
if (other)
errx(1, "\"%s\" both in %s from %s(%d) and in %s from %s(%d)",
symbol->name,
symbol->objFileName, symbol->fileName, symbol->lineNo,
other->objFileName, other->fileName, other->lineNo);
ppSym = &(tHash[calchash(tzName)]);
while (*ppSym) {
if (strcmp(tzName, (*ppSym)->pzName))
ppSym = &((*ppSym)->pNext);
else
return ((*ppSym)->nValue);
}
/* If not, add it */
bool collided = hash_AddElement(symbols, symbol->name, symbol);
errx(1,
"%s(%ld) : Unknown symbol '%s'",
pPatch->pzFilename, pPatch->nLineNo,
tzName);
if (beVerbose && collided)
warnx("Symbol hashmap collision occurred!");
}
int32_t sym_GetBank(struct sPatch *pPatch, char *tzName)
struct Symbol *sym_GetSymbol(char const *name)
{
struct ISymbol **ppSym;
ppSym = &(tHash[calchash(tzName)]);
while (*ppSym) {
if (strcmp(tzName, (*ppSym)->pzName))
ppSym = &((*ppSym)->pNext);
else
return ((*ppSym)->nBank);
}
errx(1,
"%s(%ld) : Unknown symbol '%s'",
pPatch->pzFilename, pPatch->nLineNo,
tzName);
return (struct Symbol *)hash_GetElement(symbols, name);
}
void sym_CreateSymbol(char *tzName, int32_t nValue, int32_t nBank,
char *tzObjFileName, char *tzFileName, uint32_t nFileLine)
void sym_CleanupSymbols(void)
{
if (strcmp(tzName, "@") == 0)
return;
struct ISymbol **ppSym;
ppSym = &(tHash[calchash(tzName)]);
while (*ppSym) {
if (strcmp(tzName, (*ppSym)->pzName)) {
ppSym = &((*ppSym)->pNext);
} else {
if (nBank == -1)
return;
errx(1, "'%s' in both %s : %s(%d) and %s : %s(%d)",
tzName, tzObjFileName, tzFileName, nFileLine,
(*ppSym)->tzObjFileName,
(*ppSym)->tzFileName, (*ppSym)->nFileLine);
}
}
*ppSym = malloc(sizeof **ppSym);
if (*ppSym != NULL) {
(*ppSym)->pzName = malloc(strlen(tzName) + 1);
if ((*ppSym)->pzName != NULL) {
strcpy((*ppSym)->pzName, tzName);
(*ppSym)->nValue = nValue;
(*ppSym)->nBank = nBank;
(*ppSym)->pNext = NULL;
strncpy((*ppSym)->tzObjFileName, tzObjFileName,
sizeof((*ppSym)->tzObjFileName));
strncpy((*ppSym)->tzFileName, tzFileName,
sizeof((*ppSym)->tzFileName));
(*ppSym)->nFileLine = nFileLine;
}
}
hash_EmptyMap(symbols);
}