new variant: maybe-get returns null on failure
This commit is contained in:
parent
15a84e2449
commit
2b48729fd2
148
078table.subx
148
078table.subx
|
@ -13,6 +13,7 @@
|
|||
# ------------------------+---------------------------------------------------
|
||||
# abort | get get-slice
|
||||
# insert key | get-or-insert leaky-get-or-insert-slice
|
||||
# return null | maybe-get maybe-get-slice
|
||||
# Some variants may take extra args.
|
||||
|
||||
== code
|
||||
|
@ -920,4 +921,151 @@ $test-leaky-get-or-insert-slice:end:
|
|||
5d/pop-to-EBP
|
||||
c3/return
|
||||
|
||||
# if no row is found, return null (0)
|
||||
maybe-get: # table : (address stream {string, _}), key : (address string), row-size : int -> EAX : (address _)
|
||||
# pseudocode:
|
||||
# curr = table->data
|
||||
# max = &table->data[table->write]
|
||||
# while curr < max
|
||||
# if string-equal?(key, *curr)
|
||||
# return curr+4
|
||||
# curr += row-size
|
||||
# return 0
|
||||
#
|
||||
# . prolog
|
||||
55/push-EBP
|
||||
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
|
||||
# . save registers
|
||||
51/push-ECX
|
||||
52/push-EDX
|
||||
56/push-ESI
|
||||
# ESI = table
|
||||
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 8/disp8 . # copy *(EBP+8) to ESI
|
||||
# curr/ECX = table->data
|
||||
8d/copy-address 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 0xc/disp8 . # copy ESI+12 to ECX
|
||||
# max/EDX = table->data + table->write
|
||||
8b/copy 0/mod/indirect 6/rm32/ESI . . . 2/r32/EDX . . # copy *ESI to EDX
|
||||
8d/copy-address 0/mod/indirect 4/rm32/sib 1/base/ECX 2/index/EDX . 2/r32/EDX . . # copy ECX+EDX to EDX
|
||||
$maybe-get:search-loop:
|
||||
# if (curr >= max) return null
|
||||
39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX
|
||||
73/jump-if-greater-or-equal-unsigned $maybe-get:null/disp8
|
||||
# if (string-equal?(key, *curr)) return curr+4
|
||||
# . EAX = string-equal?(key, *curr)
|
||||
# . . push args
|
||||
ff 6/subop/push 0/mod/indirect 1/rm32/ECX . . . . . . # push *ECX
|
||||
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
|
||||
# . . call
|
||||
e8/call string-equal?/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
|
||||
# . if (EAX != 0) return EAX = curr+4
|
||||
3d/compare-EAX-and 0/imm32
|
||||
74/jump-if-equal $maybe-get:mismatch/disp8
|
||||
8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy ECX+4 to EAX
|
||||
eb/jump $maybe-get:end/disp8
|
||||
$maybe-get:mismatch:
|
||||
# curr += row-size
|
||||
03/add 1/mod/*+disp8 5/rm32/EBP . . . 1/r32/ECX 0x10/disp8 . # add *(EBP+16) to ECX
|
||||
# loop
|
||||
eb/jump $maybe-get:search-loop/disp8
|
||||
$maybe-get:null:
|
||||
b8/copy-to-EAX 0/imm32
|
||||
$maybe-get:end:
|
||||
# . restore registers
|
||||
5e/pop-to-ESI
|
||||
5a/pop-to-EDX
|
||||
59/pop-to-ECX
|
||||
# . epilog
|
||||
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
|
||||
5d/pop-to-EBP
|
||||
c3/return
|
||||
|
||||
test-maybe-get:
|
||||
# . prolog
|
||||
55/push-EBP
|
||||
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
|
||||
# - setup: create a table with one row
|
||||
# var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
|
||||
81 5/subop/subtract 3/mod/direct 4/rm32/ESP . . . . . 0x10/imm32 # subtract from ESP
|
||||
68/push 0x10/imm32/length
|
||||
68/push 0/imm32/read
|
||||
68/push 0/imm32/write
|
||||
89/copy 3/mod/direct 1/rm32/ECX . . . 4/r32/ESP . . # copy ESP to ECX
|
||||
# EAX = get-or-insert(table, "code", 8 bytes per row)
|
||||
# . . push args
|
||||
68/push 8/imm32/row-size
|
||||
68/push "code"/imm32
|
||||
51/push-ECX
|
||||
# . . call
|
||||
e8/call get-or-insert/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
$test-maybe-get:success:
|
||||
# - check for the same key, verify that it was reused
|
||||
# EAX = maybe-get(table, "code", 8 bytes per row)
|
||||
# . . push args
|
||||
68/push 8/imm32/row-size
|
||||
68/push "code"/imm32
|
||||
51/push-ECX
|
||||
# . . call
|
||||
e8/call maybe-get/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
# check-ints-equal(EAX - table->data, 4, msg)
|
||||
# . check-ints-equal(EAX - table, 16, msg)
|
||||
# . . push args
|
||||
68/push "F - test-maybe-get/0"/imm32
|
||||
68/push 0x10/imm32
|
||||
29/subtract 3/mod/direct 0/rm32/EAX . . . 1/r32/ECX . . # subtract ECX from EAX
|
||||
50/push-EAX
|
||||
# . . call
|
||||
e8/call check-ints-equal/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
# no new row inserted
|
||||
# . check-ints-equal(table->write, row-size = 8, msg)
|
||||
# . . push args
|
||||
68/push "F - test-maybe-get/1"/imm32
|
||||
68/push 8/imm32/row-size
|
||||
ff 6/subop/push 0/mod/indirect 1/rm32/ECX . . . . . . # push *ECX
|
||||
# . . call
|
||||
e8/call check-ints-equal/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
# check-string-equal(*table->data, "code", msg)
|
||||
# . . push args
|
||||
68/push "F - test-maybe-get/2"/imm32
|
||||
68/push "code"/imm32
|
||||
ff 6/subop/push 1/mod/*+disp8 1/rm32/ECX . . . . 0xc/disp8 . # push *(ECX+12)
|
||||
# . . call
|
||||
e8/call check-string-equal/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
$test-maybe-get:failure:
|
||||
# - search for a new key
|
||||
# EAX = maybe-get(table, "data", 8 bytes per row)
|
||||
# . . push args
|
||||
68/push 8/imm32/row-size
|
||||
68/push "data"/imm32
|
||||
51/push-ECX
|
||||
# . . call
|
||||
e8/call maybe-get/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
# check-ints-equal(EAX, 0, msg)
|
||||
# . . push args
|
||||
68/push "F - test-maybe-get/3"/imm32
|
||||
68/push 0/imm32
|
||||
50/push-EAX
|
||||
# . . call
|
||||
e8/call check-ints-equal/disp32
|
||||
# . . discard args
|
||||
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
|
||||
$test-maybe-get:end:
|
||||
# . epilog
|
||||
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
|
||||
5d/pop-to-EBP
|
||||
c3/return
|
||||
|
||||
# . . vim:nowrap:textwidth=0
|
||||
|
|
BIN
apps/assort
BIN
apps/assort
Binary file not shown.
BIN
apps/crenshaw2-1
BIN
apps/crenshaw2-1
Binary file not shown.
Binary file not shown.
BIN
apps/desugar
BIN
apps/desugar
Binary file not shown.
BIN
apps/dquotes
BIN
apps/dquotes
Binary file not shown.
BIN
apps/factorial
BIN
apps/factorial
Binary file not shown.
BIN
apps/handle
BIN
apps/handle
Binary file not shown.
BIN
apps/survey
BIN
apps/survey
Binary file not shown.
BIN
apps/tests
BIN
apps/tests
Binary file not shown.
Loading…
Reference in New Issue