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|
;--------------------------------------------------------
; File Created by SDCC : free open source ANSI-C Compiler
; Version 3.9.3 #11345 (Linux)
;--------------------------------------------------------
.module realloc
.optsdcc -mstm8
;--------------------------------------------------------
; Public variables in this module
;--------------------------------------------------------
.globl ___memcpy
.globl _memmove
.globl _free
.globl _malloc
.globl _realloc
;--------------------------------------------------------
; ram data
;--------------------------------------------------------
.area DATA
;--------------------------------------------------------
; ram data
;--------------------------------------------------------
.area INITIALIZED
;--------------------------------------------------------
; absolute external ram data
;--------------------------------------------------------
.area DABS (ABS)
; default segment ordering for linker
.area HOME
.area GSINIT
.area GSFINAL
.area CONST
.area INITIALIZER
.area CODE
;--------------------------------------------------------
; global & static initialisations
;--------------------------------------------------------
.area HOME
.area GSINIT
.area GSFINAL
.area GSINIT
;--------------------------------------------------------
; Home
;--------------------------------------------------------
.area HOME
.area HOME
;--------------------------------------------------------
; code
;--------------------------------------------------------
.area CODE
; ../realloc.c: 56: void *realloc(void *ptr, size_t size)
; -----------------------------------------
; function realloc
; -----------------------------------------
_realloc:
sub sp, #20
; ../realloc.c: 69: if(!ptr)
ldw x, (0x18, sp)
jrne 00102$
; ../realloc.c: 70: return(malloc(size));
ldw x, (0x1a, sp)
pushw x
callf _malloc
addw sp, #2
jpf 00132$
00102$:
; ../realloc.c: 72: if(!size)
ldw x, (0x1a, sp)
jrne 00104$
; ../realloc.c: 74: free(ptr);
ldw x, (0x18, sp)
pushw x
callf _free
addw sp, #2
; ../realloc.c: 75: return(0);
clrw x
jpf 00132$
00104$:
; ../realloc.c: 78: prev_free = 0, pf = 0;
clrw x
ldw (0x01, sp), x
clrw x
ldw (0x03, sp), x
; ../realloc.c: 79: for(h = __sdcc_heap_free, f = &__sdcc_heap_free; h && h < ptr; prev_free = h, pf = f, f = &(h->next_free), h = h->next_free); // Find adjacent blocks in free list
ldw x, ___sdcc_heap_free+0
ldw (0x13, sp), x
ldw x, #(___sdcc_heap_free + 0)
ldw (0x05, sp), x
00130$:
ldw x, (0x13, sp)
jreq 00105$
ldw y, (0x18, sp)
ldw (0x11, sp), y
ldw x, (0x13, sp)
cpw x, (0x11, sp)
jrnc 00105$
ldw y, (0x13, sp)
ldw (0x01, sp), y
ldw y, (0x05, sp)
ldw (0x03, sp), y
ldw x, (0x13, sp)
incw x
incw x
ldw (0x05, sp), x
ldw x, (x)
ldw (0x13, sp), x
jra 00130$
00105$:
; ../realloc.c: 80: next_free = h;
ldw y, (0x13, sp)
ldw (0x07, sp), y
; ../realloc.c: 82: if(!size || size + offsetof(struct header, next_free) < size)
ldw x, (0x1a, sp)
jreq 00106$
incw x
incw x
cpw x, (0x1a, sp)
jrnc 00107$
00106$:
; ../realloc.c: 83: return(0);
clrw x
jpf 00132$
00107$:
; ../realloc.c: 84: blocksize = size + offsetof(struct header, next_free);
; ../realloc.c: 85: if(blocksize < sizeof(struct header)) // Requiring a minimum size makes it easier to implement free(), and avoid memory leaks.
ldw (0x09, sp), x
cpw x, #0x0004
jrnc 00110$
; ../realloc.c: 86: blocksize = sizeof(struct header);
ldw x, #0x0004
ldw (0x09, sp), x
00110$:
; ../realloc.c: 88: h = (void HEAPSPACE *)((char HEAPSPACE *)(ptr) - offsetof(struct header, next_free));
ldw x, (0x18, sp)
decw x
decw x
; ../realloc.c: 89: oldblocksize = (char HEAPSPACE *)(h->next) - (char HEAPSPACE *)h;
ldw (0x0b, sp), x
ldw x, (x)
ldw (0x0d, sp), x
ldw y, (0x0b, sp)
ldw (0x0f, sp), y
subw x, (0x0f, sp)
; ../realloc.c: 91: maxblocksize = oldblocksize;
ldw (0x11, sp), x
ldw (0x13, sp), x
; ../realloc.c: 92: if(prev_free && prev_free->next == h) // Can merge with previous block
ldw x, (0x01, sp)
jreq 00112$
ldw x, (x)
cpw x, (0x0b, sp)
jrne 00112$
; ../realloc.c: 93: maxblocksize += (char HEAPSPACE *)h - (char HEAPSPACE *)prev_free;
ldw x, (0x01, sp)
negw x
addw x, (0x0f, sp)
addw x, (0x11, sp)
ldw (0x13, sp), x
00112$:
; ../realloc.c: 94: if(next_free == h->next) // Can merge with next block
ldw x, (0x07, sp)
cpw x, (0x0d, sp)
jrne 00115$
; ../realloc.c: 95: maxblocksize += (char HEAPSPACE *)(next_free->next) - (char HEAPSPACE *)next_free;
ldw x, (0x07, sp)
ldw x, (x)
ldw y, (0x07, sp)
ldw (0x0f, sp), y
subw x, (0x0f, sp)
addw x, (0x13, sp)
ldw (0x13, sp), x
00115$:
; ../realloc.c: 97: if(blocksize <= maxblocksize) // Can resize in place.
ldw x, (0x09, sp)
cpw x, (0x13, sp)
jrule 00247$
jpf 00125$
00247$:
; ../realloc.c: 99: if(prev_free && prev_free->next == h) // Always move into previous block to defragment
ldw x, (0x01, sp)
jreq 00117$
ldw x, (x)
cpw x, (0x0b, sp)
jrne 00117$
; ../realloc.c: 101: memmove(prev_free, h, blocksize <= oldblocksize ? blocksize : oldblocksize);
ldw x, (0x09, sp)
cpw x, (0x11, sp)
jrugt 00134$
ldw y, (0x09, sp)
ldw (0x11, sp), y
00134$:
ldw y, (0x0b, sp)
ldw x, (0x01, sp)
ld a, (0x12, sp)
push a
ld a, (0x12, sp)
push a
pushw y
pushw x
callf _memmove
addw sp, #6
; ../realloc.c: 102: h = prev_free;
ldw y, (0x01, sp)
ldw (0x0b, sp), y
; ../realloc.c: 103: *pf = next_free;
ldw x, (0x03, sp)
ldw y, (0x07, sp)
ldw (x), y
; ../realloc.c: 104: f = pf;
ldw y, (0x03, sp)
ldw (0x05, sp), y
00117$:
; ../realloc.c: 107: if(next_free && next_free == h->next) // Merge with following block
ldw x, (0x07, sp)
jreq 00120$
ldw x, (0x0b, sp)
ldw x, (x)
cpw x, (0x07, sp)
jrne 00120$
; ../realloc.c: 109: h->next = next_free->next;
ldw x, (0x07, sp)
ldw x, (x)
ldw y, (0x0b, sp)
ldw (y), x
; ../realloc.c: 110: *f = next_free->next_free;
ldw x, (0x07, sp)
ldw x, (0x2, x)
ldw y, (0x05, sp)
ldw (y), x
00120$:
; ../realloc.c: 113: if(maxblocksize >= blocksize + sizeof(struct header)) // Create new block from free space
ldw x, (0x09, sp)
addw x, #0x0004
ldw (0x11, sp), x
ldw x, (0x13, sp)
cpw x, (0x11, sp)
jrc 00123$
; ../realloc.c: 115: header_t *const newheader = (header_t *const)((char HEAPSPACE *)h + blocksize);
ldw x, (0x0b, sp)
addw x, (0x09, sp)
ldw (0x13, sp), x
; ../realloc.c: 116: newheader->next = h->next;
ldw x, (0x0b, sp)
ldw x, (x)
ldw y, (0x13, sp)
ldw (y), x
; ../realloc.c: 117: newheader->next_free = *f;
ldw x, (0x13, sp)
incw x
incw x
ldw y, (0x05, sp)
ldw y, (y)
ldw (x), y
; ../realloc.c: 118: *f = newheader;
ldw x, (0x05, sp)
ldw y, (0x13, sp)
ldw (x), y
; ../realloc.c: 119: h->next = newheader;
ldw x, (0x0b, sp)
ldw y, (0x13, sp)
ldw (x), y
00123$:
; ../realloc.c: 122: return(&(h->next_free));
ldw x, (0x0b, sp)
incw x
incw x
jra 00132$
00125$:
; ../realloc.c: 125: if(ret = malloc(size))
ldw x, (0x1a, sp)
pushw x
callf _malloc
addw sp, #2
ldw (0x13, sp), x
tnzw x
jreq 00127$
; ../realloc.c: 127: size_t oldsize = oldblocksize - offsetof(struct header, next_free);
ldw x, (0x11, sp)
decw x
decw x
; ../realloc.c: 128: memcpy(ret, ptr, size <= oldsize ? size : oldsize);
cpw x, (0x1a, sp)
jrc 00136$
ldw x, (0x1a, sp)
00136$:
pushw x
ldw x, (0x1a, sp)
pushw x
ldw x, (0x17, sp)
pushw x
callf ___memcpy
addw sp, #6
; ../realloc.c: 129: free(ptr);
ldw x, (0x18, sp)
pushw x
callf _free
addw sp, #2
; ../realloc.c: 130: return(ret);
ldw x, (0x13, sp)
; ../realloc.c: 133: return(0);
.byte 0x21
00127$:
clrw x
00132$:
; ../realloc.c: 134: }
addw sp, #20
retf
.area CODE
.area CONST
.area INITIALIZER
.area CABS (ABS)
|
