# A table is a stream of (key, value) rows.
#
# Each row consists of a 4-byte key (address to a string) and a variable-size
# value.
#
# Accessing the table performs a linear scan for a key string, and always
# requires passing in the row size.
#
# Table primitives have the form <variant>(stream, <arg>, row-size, ...) -> address/EAX
#
# The following table shows available options for <variant>:
# if not found: | arg=string arg=slice
# ------------------------+---------------------------------------------------
# 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
# instruction effective address register displacement immediate
# . op subop mod rm32 base index scale r32
# . 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes
# if no row is found, abort
get: # table : (address stream {string, _}), key : (address string), row-size : int, abort-message-prefix : (address string) -> 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
# abort
#
# . 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
$get:search-loop:
# if (curr >= max) abort
39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX
73/jump-if-greater-or-equal-unsigned $get:abort/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 $get:mismatch/disp8
8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy ECX+4 to EAX
eb/jump $get:end/disp8
$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 $get:search-loop/disp8
$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
$get:abort:
# . _write(2/stderr, abort-message-prefix)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0x14/disp8 . # push *(EBP+20)
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . _write(2/stderr, error)
# . . push args
68/push ": get: key not found: "/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . _write(2/stderr, key)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . _write(2/stderr, "\n")
# . . push args
68/push "\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . syscall(exit, 1)
bb/copy-to-EBX 1/imm32
b8/copy-to-EAX 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
test-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 a couple of keys
# 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
# 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
# insert(table, "data", 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
68/push "data"/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-get:check1:
# EAX = 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 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-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
$test-get:check2:
# EAX = 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 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, 12, msg)
# . check-ints-equal(EAX - table, 24, msg)
# . . push args
68/push "F - test-get/1"/imm32
68/push 0x18/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
$test-get:end:
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
# if no row is found, abort
get-slice: # table : (address stream {string, _}), key : (address slice), row-size : int, abort-message-prefix : (address string) -> EAX : (address _)
# pseudocode:
# curr = table->data
# max = &table->data[table->write]
# while curr < max
# if slice-equal?(key, *curr)
# return curr+4
# curr += row-size
# abort
#
# . 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
$get-slice:search-loop:
# if (curr >= max) abort
39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX
73/jump-if-greater-or-equal-unsigned $get-slice:abort/disp8
# if (slice-equal?(key, *curr)) return curr+4
# . EAX = slice-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 slice-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 $get-slice:mismatch/disp8
8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy ECX+4 to EAX
eb/jump $get-slice:end/disp8
$get-slice: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 $get-slice:search-loop/disp8
$get-slice: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
$get-slice:abort:
# . _write(2/stderr, abort-message-prefix)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0x14/disp8 . # push *(EBP+20)
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . _write(2/stderr, error)
# . . push args
68/push "get-slice: key not found: "/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . write-slice-buffered(Stderr, key)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
68/push Stderr/imm32
# . . call
e8/call write-slice-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . flush(Stderr)
# . . push args
68/push Stderr/imm32
# . . call
e8/call flush/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# . _write(2/stderr, "\n")
# . . push args
68/push "\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . syscall(exit, 1)
bb/copy-to-EBX 1/imm32
b8/copy-to-EAX 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
test-get-slice:
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# - setup: create a table with a couple of keys
# 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
# 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
# insert(table, "data", 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
68/push "data"/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-get-slice:check1:
# (EAX..EDX) = "code"
b8/copy-to-EAX "code"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
# EAX = get-slice(table, "code", 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call get-slice/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) # first row's value slot returned
# . check-ints-equal(EAX - table, 16, msg)
# . . push args
68/push "F - test-get-slice/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
$test-get-slice:check2:
# (EAX..EDX) = "data"
b8/copy-to-EAX "data"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
# EAX = get-slice(table, "data" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call get-slice/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# check-ints-equal(EAX - table->data, 12, msg)
# . check-ints-equal(EAX - table, 24, msg)
# . . push args
68/push "F - test-get-slice/1"/imm32
68/push 0x18/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
$test-get-slice:end:
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
# if no row is found, save 'key' to the next available row
# if there are no rows free, abort
# return the address of the value
# Beware: assume keys are immutable; they're inserted by reference
# TODO: pass in an allocation descriptor
get-or-insert: # 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
# if table->write >= table->length
# abort
# zero-out(max, row-size)
# *max = key
# table->write += row-size
# return max+4
#
# . 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
$get-or-insert:search-loop:
# if (curr >= max) break
39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX
73/jump-if-greater-or-equal-unsigned $get-or-insert:not-found/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 $get-or-insert:mismatch/disp8
8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy ECX+4 to EAX
eb/jump $get-or-insert:end/disp8
$get-or-insert: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 $get-or-insert:search-loop/disp8
$get-or-insert:not-found:
# result/EAX = 0
31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX
# if (table->write >= table->length) abort
8b/copy 0/mod/indirect 6/rm32/ESI . . . 1/r32/ECX . . # copy *ESI to ECX
3b/compare 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 8/disp8 . # compare ECX with *(ESI+8)
73/jump-if-greater-or-equal-unsigned $get-or-insert:abort/disp8
# zero-out(max, row-size)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0x10/disp8 . # push *(EBP+16)
52/push-EDX
# . . call
e8/call zero-out/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# *max = key
# . EAX = key
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 0/r32/EAX 0xc/disp8 . # copy *(EBP+12) to EAX
# . *max = EAX
89/copy 0/mod/indirect 2/rm32/EDX . . . 0/r32/EAX . . # copy EAX to *EDX
# table->write += row-size
# . EAX = row-size
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 0/r32/EAX 0x10/disp8 . # copy *(EBP+16) to EAX
# . table->write += EAX
01/add 0/mod/indirect 6/rm32/ESI . . . 0/r32/EAX . . # add EAX to *ESI
# return max+4
# . EAX = max
89/copy 3/mod/direct 0/rm32/EAX . . . 2/r32/EDX . . # copy EDX to EAX
# . EAX += 4
05/add-to-EAX 4/imm32
$get-or-insert: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
$get-or-insert:abort:
# . _write(2/stderr, error)
# . . push args
68/push "get-or-insert: table is full\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . syscall(exit, 1)
bb/copy-to-EBX 1/imm32
b8/copy-to-EAX 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
test-get-or-insert:
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# 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
$test-get-or-insert:first-call:
# - start with an empty table, insert one key, verify that it was inserted
# 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
# check-ints-equal(EAX - table->data, 4, msg) # first row's value slot returned
# . check-ints-equal(EAX - table, 16, msg)
# . . push args
68/push "F - test-get-or-insert/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
$test-get-or-insert:check2:
# check-ints-equal(table->write, row-size = 8, msg)
# . . push args
68/push "F - test-get-or-insert/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-get-or-insert/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-get-or-insert:second-call:
# - insert the same key again, verify that it was reused
# 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
# check-ints-equal(EAX - table->data, 4, msg)
# . check-ints-equal(EAX - table, 16, msg)
# . . push args
68/push "F - test-get-or-insert/3"/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-get-or-insert/4"/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-get-or-insert/5"/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-get-or-insert:third-call:
# - insert a new key, verify that it was inserted
# EAX = get-or-insert(table, "data", 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
68/push "data"/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
# table gets a new row
# check-ints-equal(EAX - table->data, 12, msg) # second row's value slot returned
# . check-ints-equal(EAX - table, 24, msg)
# . . push args
68/push "F - test-get-or-insert/6"/imm32
68/push 0x18/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
# check-ints-equal(table->write, 2 rows = 16, msg)
# . . push args
68/push "F - test-get-or-insert/7"/imm32
68/push 0x10/imm32/two-rows
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+8, "data", msg)
# check-string-equal(*(table+20), "data", msg)
# . . push args
68/push "F - test-get-or-insert/8"/imm32
68/push "data"/imm32
ff 6/subop/push 1/mod/*+disp8 1/rm32/ECX . . . . 0x14/disp8 . # push *(ECX+20)
# . . 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-get-or-insert:end:
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
# if no row is found, save 'key' in the next available row
# if there are no rows free, abort
# WARNING: leaks memory
# TODO: pass in an allocation descriptor
leaky-get-or-insert-slice: # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
# pseudocode:
# curr = table->data
# max = &table->data[table->write]
# while curr < max
# if slice-equal?(key, *curr)
# return curr+4
# curr += row-size
# if table->write >= table->length
# abort
# zero-out(max, row-size)
# *max = slice-to-string(Heap, key)
# table->write += row-size
# return max+4
#
# . 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
$leaky-get-or-insert-slice:search-loop:
# if (curr >= max) break
39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX
73/jump-if-greater-or-equal-unsigned $leaky-get-or-insert-slice:not-found/disp8
# if (slice-equal?(key, *curr)) return curr+4
# . EAX = slice-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 slice-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 $leaky-get-or-insert-slice:mismatch/disp8
8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy ECX+4 to EAX
eb/jump $leaky-get-or-insert-slice:end/disp8
$leaky-get-or-insert-slice: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 $leaky-get-or-insert-slice:search-loop/disp8
$leaky-get-or-insert-slice:not-found:
# result/EAX = 0
31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX
# if (table->write >= table->length) abort
8b/copy 0/mod/indirect 6/rm32/ESI . . . 1/r32/ECX . . # copy *ESI to ECX
3b/compare 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 8/disp8 . # compare ECX with *(ESI+8)
7d/jump-if-greater-or-equal $leaky-get-or-insert-slice:abort/disp8
# zero-out(max, row-size)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0x10/disp8 . # push *(EBP+16)
52/push-EDX
# . . call
e8/call zero-out/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# *max = slice-to-string(Heap, key)
# . EAX = slice-to-string(Heap, key)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
68/push Heap/imm32
# . . call
e8/call slice-to-string/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . *max = EAX
89/copy 0/mod/indirect 2/rm32/EDX . . . 0/r32/EAX . . # copy EAX to *EDX
# table->write += row-size
# . EAX = row-size
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 0/r32/EAX 0x10/disp8 . # copy *(EBP+16) to EAX
# . table->write += EAX
01/add 0/mod/indirect 6/rm32/ESI . . . 0/r32/EAX . . # add EAX to *ESI
# return max+4
# . EAX = max
89/copy 3/mod/direct 0/rm32/EAX . . . 2/r32/EDX . . # copy EDX to EAX
# . EAX += 4
05/add-to-EAX 4/imm32
$leaky-get-or-insert-slice: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
$leaky-get-or-insert-slice:abort:
# . _write(2/stderr, error)
# . . push args
68/push "leaky-get-or-insert-slice: table is full\n"/imm32
68/push 2/imm32/stderr
# . . call
e8/call _write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# . syscall(exit, 1)
bb/copy-to-EBX 1/imm32
b8/copy-to-EAX 1/imm32/exit
cd/syscall 0x80/imm8
# never gets here
test-leaky-get-or-insert-slice:
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# 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..EDX) = "code"
b8/copy-to-EAX "code"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
$test-leaky-get-or-insert-slice:first-call:
# - start with an empty table, insert one key, verify that it was inserted
# EAX = leaky-get-or-insert-slice(table, "code" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call leaky-get-or-insert-slice/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) # first row's value slot returned
# . check-ints-equal(EAX - table, 16, msg)
# . . push args
68/push "F - test-leaky-get-or-insert-slice/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
$test-leaky-get-or-insert-slice:check2:
# check-ints-equal(table->write, row-size = 8, msg)
# . . push args
68/push "F - test-leaky-get-or-insert-slice/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-leaky-get-or-insert-slice/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-leaky-get-or-insert-slice:second-call:
# - insert the same key again, verify that it was reused
# EAX = leaky-get-or-insert-slice(table, "code" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call leaky-get-or-insert-slice/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-leaky-get-or-insert-slice/3"/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-leaky-get-or-insert-slice/4"/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-leaky-get-or-insert-slice/5"/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-leaky-get-or-insert-slice:third-call:
# - insert a new key, verify that it was inserted
# (EAX..EDX) = "data"
b8/copy-to-EAX "data"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
# EAX = leaky-get-or-insert-slice(table, "data" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call leaky-get-or-insert-slice/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# table gets a new row
# check-ints-equal(EAX - table->data, 12, msg) # second row's value slot returned
# . check-ints-equal(EAX - table, 24, msg)
# . . push args
68/push "F - test-leaky-get-or-insert-slice/6"/imm32
68/push 0x18/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
# check-ints-equal(table->write, 2 rows = 16, msg)
# . . push args
68/push "F - test-leaky-get-or-insert-slice/7"/imm32
68/push 0x10/imm32/two-rows
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+8, "data", msg)
# check-string-equal(*(table+20), "data", msg)
# . . push args
68/push "F - test-leaky-get-or-insert-slice/8"/imm32
68/push "data"/imm32
ff 6/subop/push 1/mod/*+disp8 1/rm32/ECX . . . . 0x14/disp8 . # push *(ECX+20)
# . . 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-leaky-get-or-insert-slice:end:
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
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
# if no row is found, return null (0)
maybe-get-slice: # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
# pseudocode:
# curr = table->data
# max = &table->data[table->write]
# while curr < max
# if slice-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-slice: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-slice:null/disp8
# if (slice-equal?(key, *curr)) return curr+4
# . EAX = slice-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 slice-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-slice: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-slice:end/disp8
$maybe-get-slice: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-slice:search-loop/disp8
$maybe-get-slice:null:
b8/copy-to-EAX 0/imm32
$maybe-get-slice: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-slice:
# . 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
# 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-slice:success:
# - check for the same key, verify that it was reused
# (EAX..EDX) = "code"
b8/copy-to-EAX "code"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
# EAX = maybe-get-slice(table, "code" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call maybe-get-slice/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-slice/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-slice/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-slice/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-slice:failure:
# - search for a new key
# (EAX..EDX) = "data"
b8/copy-to-EAX "data"/imm32
8b/copy 0/mod/indirect 0/rm32/EAX . . . 2/r32/EDX . . # copy *EAX to EDX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 2/index/EDX . 2/r32/EDX 4/disp8 . # copy EAX+EDX+4 to EDX
05/add-to-EAX 4/imm32
# var slice/EDX = {EAX, EDX}
52/push-EDX
50/push-EAX
89/copy 3/mod/direct 2/rm32/EDX . . . 4/r32/ESP . . # copy ESP to EDX
# EAX = maybe-get-slice(table, "data" slice, 8 bytes per row)
# . . push args
68/push 8/imm32/row-size
52/push-EDX
51/push-ECX
# . . call
e8/call maybe-get-slice/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-slice/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-slice: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