From 46fe949677745250de387994657de2004fe3b29b Mon Sep 17 00:00:00 2001 From: notaz Date: Tue, 19 Sep 2023 01:34:44 +0300 Subject: [PATCH] psxbios: maybe more accurate malloc --- libpcsxcore/psxbios.c | 176 +++++++++++++++++++----------------------- 1 file changed, 81 insertions(+), 95 deletions(-) diff --git a/libpcsxcore/psxbios.c b/libpcsxcore/psxbios.c index fb7d13d1..a41cf54e 100644 --- a/libpcsxcore/psxbios.c +++ b/libpcsxcore/psxbios.c @@ -292,8 +292,10 @@ static u32 floodchk; #define A_HEAP_BASE 0x9000 #define A_HEAP_SIZE 0x9004 #define A_HEAP_END 0x9008 -#define A_HEAP_FLAG 0x900c +#define A_HEAP_INIT_FLG 0x900c #define A_RND_SEED 0x9010 +#define A_HEAP_FRSTCHNK 0xb060 +#define A_HEAP_CURCHNK 0xb064 #define A_CONF_TCB 0xb940 #define A_CONF_EvCB 0xb944 #define A_CONF_SP 0xb948 @@ -1214,114 +1216,98 @@ void psxBios_qsort() { // 0x31 pc0 = ra; } -// this isn't how the real bios works, but maybe good enough +static int malloc_heap_grow(u32 size) { + u32 heap_addr, heap_end, heap_addr_new; + + heap_addr = loadRam32(A_HEAP_BASE); + heap_end = loadRam32(A_HEAP_END); + heap_addr_new = heap_addr + 4 + size; + if (heap_addr_new >= heap_end) + return -1; + storeRam32(A_HEAP_BASE, heap_addr_new); + storeRam32(heap_addr - 4, size | 1); + storeRam32(heap_addr + size, ~1); // terminator + return 0; +} + static void psxBios_malloc() { // 0x33 - u32 *heap_addr, *heap_end; - u32 *chunk, *newchunk = NULL; - unsigned int dsize = 0, csize, cstat; - int colflag; - PSXBIOS_LOG("psxBios_%s %x\n", biosA0n[0x33], a0); - heap_addr = loadRam32ptr(A_HEAP_BASE); - heap_end = loadRam32ptr(A_HEAP_END); - if (heap_addr >= heap_end) { - v0 = 0; - pc0 = ra; - return; - } + u32 size = (a0 + 3) & ~3; + u32 limit = 32*1024; + u32 tries = 2, i; + u32 ret; - // scan through heap and combine free chunks of space - chunk = heap_addr; - colflag = 0; - while(chunk < heap_end) { - // get size and status of actual chunk - csize = ((u32)*chunk) & 0xfffffffc; - cstat = ((u32)*chunk) & 1; - - // most probably broken heap descriptor - // this fixes Burning Road - if (*chunk == 0) { - newchunk = chunk; - dsize = ((uptr)heap_end - (uptr)chunk) - 4; - colflag = 1; - break; + PSXBIOS_LOG("psxBios_%s %d\n", biosA0n[0x33], a0); + + if (!loadRam32(A_HEAP_INIT_FLG)) { + u32 heap_addr = loadRam32(A_HEAP_BASE); + storeRam32(heap_addr, ~1); + storeRam32(A_HEAP_FRSTCHNK, heap_addr); + storeRam32(A_HEAP_CURCHNK, heap_addr); + storeRam32(A_HEAP_BASE, heap_addr + 4); + if (malloc_heap_grow(size)) { + PSXBIOS_LOG("malloc: init OOM\n"); + mips_return_c(0, 20); + return; } + storeRam32(A_HEAP_INIT_FLG, 1); + } - // it's a free chunk - if(cstat == 1) { - if(colflag == 0) { - newchunk = chunk; - dsize = csize; - colflag = 1; // let's begin a new collection of free memory + for (i = 0; tries > 0 && i < limit; i++) + { + u32 chunk = loadRam32(A_HEAP_CURCHNK); + u32 chunk_hdr = loadRam32(chunk); + u32 next_chunk = chunk + 4 + (chunk_hdr & ~3); + u32 next_chunk_hdr = loadRam32(next_chunk); + use_cycles(20); + //printf(" c %08x %08x\n", chunk, chunk_hdr); + if (chunk_hdr & 1) { + // free chunk + if (chunk_hdr > (size | 1)) { + // split + u32 p2size = (chunk_hdr & ~3) - size - 4; + storeRam32(chunk + 4 + size, p2size | 1); + chunk_hdr = size | 1; + } + if (chunk_hdr == (size | 1)) { + storeRam32(chunk, size); + break; + } + // chunk too small + if (next_chunk_hdr & 1) { + // merge + u32 msize = (chunk_hdr & ~3) + 4 + (next_chunk_hdr & ~3); + storeRam32(chunk, msize | 1); + continue; } - else dsize += (csize+4); // add the new size including header } - // not a free chunk: did we start a collection ? + if (chunk_hdr == ~1) { + // last chunk + if (tries == 2) + storeRam32(A_HEAP_CURCHNK, loadRam32(A_HEAP_FRSTCHNK)); + tries--; + } else { - if(colflag == 1) { // collection is over - colflag = 0; - *newchunk = SWAP32(dsize | 1); - } + // go to the next chunk + storeRam32(A_HEAP_CURCHNK, next_chunk); } - - // next chunk - chunk = (u32*)((uptr)chunk + csize + 4); } - // if neccessary free memory on end of heap - if (colflag == 1) - *newchunk = SWAP32(dsize | 1); - - chunk = heap_addr; - csize = ((u32)*chunk) & 0xfffffffc; - cstat = ((u32)*chunk) & 1; - dsize = (a0 + 3) & 0xfffffffc; - // exit on uninitialized heap - if (chunk == NULL) { - printf("malloc %x,%x: Uninitialized Heap!\n", v0, a0); - v0 = 0; - pc0 = ra; - return; + if (i == limit) + ret = 0; + else if (tries == 0 && malloc_heap_grow(size)) + ret = 0; + else { + u32 chunk = loadRam32(A_HEAP_CURCHNK); + storeRam32(chunk, loadRam32(chunk) & ~3); + ret = chunk + 4; } - // search an unused chunk that is big enough until the end of the heap - while ((dsize > csize || cstat==0) && chunk < heap_end ) { - chunk = (u32*)((uptr)chunk + csize + 4); - - // catch out of memory - if(chunk >= heap_end) { - printf("malloc %x,%x: Out of memory error!\n", - v0, a0); - v0 = 0; pc0 = ra; - return; - } - - csize = ((u32)*chunk) & 0xfffffffc; - cstat = ((u32)*chunk) & 1; - } - - // allocate memory - if(dsize == csize) { - // chunk has same size - *chunk &= 0xfffffffc; - } else if (dsize > csize) { - v0 = 0; pc0 = ra; - return; - } else { - // split free chunk - *chunk = SWAP32(dsize); - newchunk = (u32*)((uptr)chunk + dsize + 4); - *newchunk = SWAP32(((csize - dsize - 4) & 0xfffffffc) | 1); - } - - // return pointer to allocated memory - v0 = ((uptr)chunk - (uptr)psxM) + 4; - v0|= 0x80000000; - //printf ("malloc %x,%x\n", v0, a0); - pc0 = ra; + PSXBIOS_LOG(" -> %08x\n", ret); + mips_return_c(ret, 40); } static void psxBios_free() { // 0x34 - PSXBIOS_LOG("psxBios_%s %x (%x bytes)\n", biosA0n[0x34], a0, loadRam32(a0 - 4)); + PSXBIOS_LOG("psxBios_%s %x (%d bytes)\n", biosA0n[0x34], a0, loadRam32(a0 - 4)); storeRam32(a0 - 4, loadRam32(a0 - 4) | 1); // set chunk to free mips_return_void_c(5); } @@ -1376,7 +1362,7 @@ static void psxBios_InitHeap() { // 0x39 storeRam32(A_HEAP_BASE, a0); storeRam32(A_HEAP_SIZE, a1); storeRam32(A_HEAP_END, a0 + (a1 & ~3) + 4); - storeRam32(A_HEAP_FLAG, 0); + storeRam32(A_HEAP_INIT_FLG, 0); storeRam32(a0, 0); mips_return_void_c(14); -- 2.39.2