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symtable.s
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symtable.s
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@ Copyright (c) 2009, Gerard Lledo Vives <[email protected]>
@ This program is open source. For license terms, see the LICENSE file.
.include "regdefs.asi"
.include "flags.asi"
.include "lib.asi"
.macro GETFL flag
ldr r0, [stp, #32]
tst r0, \flag
.endm
.macro SETFL flag
ldr r0, [stp, #32]
orr r0, \flag
str r0, [stp, #32]
.endm
.text
.align 2
.global symtable_init
.global symtable_lookup
.global symtable_next
.global symtable_run
.global symtable_get_fun
.global symtable_set_fun
.global symtable_get_name
.global symtable_set_name
.global symtable_getflag_interp
.global symtable_setflag_interp
.global symtable_set_null
.global symtable_restart
@ This module should, ideally, hide any implementation specifics of the
@ symbol table. The format of a register is as follows:
@
@ 32B 4B 4B
@ +---------------------------------+----+----+
@ | Symbol name | FL | PT |
@ +---------------------------------+----+----+
@ FL => Flags field.
@ PT => Pointer to the subroutine.
@ The symbol name is 32B long as this is the standard symbol name size.
symtable_init:
push {lr}
sbrk #0x1000
mov stp, r0
pop {lr}
bx lr
@ Leave $stp pointing to the record matching $r0
symtable_lookup:
push {lr}
.Llookup_repeat:
ldr r1, [stp]
cmp r1, #0
beq .Llookup_end
mov r1, stp
bl strcmp
blne symtable_next
bne .Llookup_repeat
Z_CLEAR
.Llookup_end:
pop {lr}
bx lr
symtable_next:
add stp, #40
bx lr
@ Runs the symtable record if valid
@ If not valid, set Z
symtable_run:
push {stp, lr}
bl symtable_getflag_interp
beq .Lrun_end @ No interpretation semantics
bl symtable_get_fun
beq .Lrun_end @ No such word
mov lr, pc
bx r0
Z_CLEAR
.Lrun_end:
pop {stp, lr}
bx lr
@ Get the function pointer of the current record
@ Return in $r0, set Z accordingly
symtable_get_fun:
ldr r0, [stp, #36]
cmp r0, #0
bx lr
symtable_set_fun:
str r0, [stp, #36]
bx lr
symtable_get_name:
mov r0, stp
bx lr
symtable_set_name:
push {lr}
cmp r1, #36
movhi r1, #36
strncpy stp, r0, r1
pop {lr}
bx lr
symtable_getflag_interp:
GETFL #0x1
bx lr
symtable_setflag_interp:
SETFL #0x1
bx lr
symtable_set_null:
mov r1, #0
mov r0, #40
.Lset_null_restart:
sub r0, #4
str r1, [stp, r0]
cmp r0, #0
beq .Lset_null_restart
bx lr
symtable_restart:
bic stp, #0xff
bic stp, #0xf00
bx lr