5462619d96
We still need a few primitives, but we can implement these as needed. I'm ready to call the fake screen done.
954 lines
54 KiB
Plaintext
954 lines
54 KiB
Plaintext
# Helper to dynamically allocate memory on the heap.
|
|
#
|
|
# We'd like to be able to write tests for functions that allocate memory,
|
|
# making assertions on the precise addresses used. To achieve this we'll pass
|
|
# in an *allocation descriptor* to allocate from.
|
|
#
|
|
# Allocation descriptors are also useful outside of tests. Assembly and machine
|
|
# code are of necessity unsafe languages, and one of the most insidious kinds
|
|
# of bugs unsafe languages expose us to are dangling pointers to memory that
|
|
# has been freed and potentially even reused for something totally different.
|
|
# To reduce the odds of such "use after free" errors, SubX programs tend to not
|
|
# reclaim and reuse dynamically allocated memory. (Running out of memory is far
|
|
# easier to debug.) Long-running programs that want to reuse memory are mostly
|
|
# on their own to be careful. However, they do get one bit of help: they can
|
|
# carve out chunks of memory and then allocate from them manually using this
|
|
# very same 'allocate' helper. They just need a new allocation descriptor for
|
|
# their book-keeping.
|
|
|
|
== data
|
|
|
|
# Allocations are returned in a handle, which consists of an alloc-id and a payload.
|
|
# The alloc-id helps detect use-after-free errors.
|
|
Handle-size: # (addr int)
|
|
8/imm32
|
|
|
|
# A default allocation descriptor for programs to use.
|
|
Heap: # allocation-descriptor
|
|
# curr
|
|
0/imm32
|
|
# limit
|
|
0/imm32
|
|
|
|
# a reasonable default
|
|
Heap-size: # int
|
|
0x600000/imm32/6MB
|
|
|
|
Next-alloc-id: # int
|
|
0x100/imm32 # save a few alloc ids for fake handles
|
|
|
|
== 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
|
|
|
|
# Let's start initializing the default allocation descriptor.
|
|
|
|
Entry:
|
|
# initialize heap
|
|
# . Heap = new-segment(Heap-size)
|
|
# . . push args
|
|
68/push Heap/imm32
|
|
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Heap-size/disp32 # push *Heap-size
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
|
|
e8/call run-tests/disp32 # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
|
|
$array-equal-main:end:
|
|
# syscall(exit, Num-test-failures)
|
|
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 3/r32/ebx Num-test-failures/disp32 # copy *Num-test-failures to ebx
|
|
e8/call syscall_exit/disp32
|
|
|
|
# Allocate and clear 'n' bytes of memory from an allocation-descriptor 'ad'.
|
|
# Abort if there isn't enough memory in 'ad'.
|
|
allocate: # ad: (addr allocation-descriptor), n: int, out: (addr handle _)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
# allocate-raw(ad, n, out)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x10/disp8 . # push *(ebp+16)
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
|
|
# . . call
|
|
e8/call allocate-raw/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# eax = out->payload + 4
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0x10/disp8 . # copy *(ebp+16) to eax
|
|
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
|
|
05/add-to-eax 4/imm32
|
|
# zero-out(eax, n)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
|
|
50/push-eax
|
|
# . . call
|
|
e8/call zero-out/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
$allocate:end:
|
|
# . restore registers
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
# Claim the next 'n' bytes of memory starting at ad->curr and update ad->curr.
|
|
# Abort if there isn't enough memory in 'ad'.
|
|
allocate-raw: # ad: (addr allocation-descriptor), n: int, out: (addr handle _)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
52/push-edx
|
|
53/push-ebx
|
|
56/push-esi
|
|
57/push-edi
|
|
# ecx = ad
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
|
|
# edx = out
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 2/r32/edx 0x10/disp8 . # copy *(ebp+16) to edx
|
|
# ebx = n
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 3/r32/ebx 0xc/disp8 . # copy *(ebp+12) to ebx
|
|
# out->alloc-id = Next-alloc-id
|
|
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/eax Next-alloc-id/disp32 # copy *Next-alloc-id to eax
|
|
89/copy 0/mod/indirect 2/rm32/edx . . . 0/r32/eax . . # copy eax to *edx
|
|
# out->payload = ad->curr
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
|
|
$allocate-raw:save-payload-in-eax:
|
|
89/copy 1/mod/*+disp8 2/rm32/edx . . . 0/r32/eax 4/disp8 . # copy eax to *(edx+4)
|
|
# *out->payload = Next-alloc-id
|
|
8b/copy 1/mod/*+disp8 2/rm32/edx . . . 7/r32/edi 4/disp8 . # copy *(edx+4) to edi
|
|
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 6/r32/esi Next-alloc-id/disp32 # copy *Next-alloc-id to esi
|
|
89/copy 0/mod/indirect 7/rm32/edi . . . 6/r32/esi . . # copy esi to *edi
|
|
$allocate-raw:increment-next-alloc-id:
|
|
# increment *Next-alloc-id
|
|
ff 0/subop/increment 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 # increment *Next-alloc-id
|
|
# check if there's enough space
|
|
# TODO: move this check up before any state updates when we support error recovery
|
|
8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/eax 3/index/ebx . 0/r32/eax 4/disp8 . # copy eax+ebx+4 to eax
|
|
3b/compare 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # compare eax with *(ecx+4)
|
|
73/jump-if->=-signed $allocate-raw:abort/disp8
|
|
$allocate-raw:commit:
|
|
# ad->curr += n+4
|
|
89/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy eax to *ecx
|
|
$allocate-raw:end:
|
|
# . restore registers
|
|
5f/pop-to-edi
|
|
5e/pop-to-esi
|
|
5b/pop-to-ebx
|
|
5a/pop-to-edx
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
$allocate-raw:abort:
|
|
# . _write(2/stderr, error)
|
|
# . . push args
|
|
68/push "allocate: failed\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
|
|
e8/call syscall_exit/disp32
|
|
# never gets here
|
|
|
|
test-allocate-raw-success:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var ad/ecx: allocation-descriptor
|
|
68/push 0/imm32/limit
|
|
68/push 0/imm32/curr
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# ad = new-segment(512)
|
|
# . . push args
|
|
51/push-ecx
|
|
68/push 0x200/imm32
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# var expected-payload/ebx = ad->curr
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 3/r32/ebx . . # copy *ecx to ebx
|
|
# var h/edx: handle = {0, 0}
|
|
68/push 0/imm32
|
|
68/push 0/imm32
|
|
89/copy 3/mod/direct 2/rm32/edx . . . 4/r32/esp . . # copy esp to edx
|
|
# *Next-alloc-id = 0x34
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x34/imm32 # copy to *Next-alloc-id
|
|
# allocate-raw(ad, 3, h)
|
|
# . . push args
|
|
52/push-edx
|
|
68/push 3/imm32
|
|
51/push-ecx
|
|
# . . call
|
|
e8/call allocate-raw/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# check-ints-equal(h->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-raw-success: sets alloc-id in handle"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 2/rm32/edx . . . . . . # push *edx
|
|
# . . 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(h->payload, expected-payload, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-raw-success: sets payload in handle"/imm32
|
|
53/push-ebx
|
|
ff 6/subop/push 1/mod/*+disp8 2/rm32/edx . . . . 4/disp8 . # push *(edx+4)
|
|
# . . 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(h->payload->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-raw-success: sets alloc-id in payload"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 3/rm32/ebx . . . . . . # push *ebx
|
|
# . . 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(*Next-alloc-id, 0x35, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-raw-success: increments Next-alloc-id"/imm32
|
|
68/push 0x35/imm32
|
|
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 # push *Next-alloc-id
|
|
# . . 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(ad->curr - expected-payload, 3 + 4 for alloc-id, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-raw-success: updates allocation descriptor"/imm32
|
|
68/push 7/imm32
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
|
|
29/subtract 3/mod/direct 0/rm32/eax . . . 3/r32/ebx . . # subtract ebx 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
|
|
# clean up
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x100/imm32 # copy to *Next-alloc-id
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
lookup: # h: (handle _T) -> result/eax: (addr _T)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
51/push-ecx
|
|
# eax = 0
|
|
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
|
|
# ecx = handle->alloc_id
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
|
|
# if (ecx == 0) return 0
|
|
81 7/subop/compare 3/mod/direct 1/rm32/ecx . . . . . 0/imm32 # compare ecx
|
|
74/jump-if-= $lookup:end/disp8
|
|
# eax = handle->address (payload)
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0xc/disp8 . # copy *(ebp+12) to eax
|
|
# if (ecx != *eax) abort
|
|
39/compare 0/mod/indirect 0/rm32/eax . . . 1/r32/ecx . . # compare *eax and ecx
|
|
75/jump-if-!= $lookup:abort/disp8
|
|
# add 4 to eax
|
|
05/add-to-eax 4/imm32
|
|
$lookup:end:
|
|
# . restore registers
|
|
59/pop-to-ecx
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
$lookup:abort:
|
|
# . _write(2/stderr, msg)
|
|
# . . push args
|
|
68/push "lookup failed\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/exit-status
|
|
e8/call syscall_exit/disp32
|
|
|
|
test-lookup-success:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var ad/ebx: allocation-descriptor
|
|
68/push 0/imm32/limit
|
|
68/push 0/imm32/curr
|
|
89/copy 3/mod/direct 3/rm32/ebx . . . 4/r32/esp . . # copy esp to ebx
|
|
# ad = new-segment(512)
|
|
# . . push args
|
|
53/push-ebx
|
|
68/push 0x200/imm32
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# var handle/ecx: handle
|
|
68/push 0/imm32/address
|
|
68/push 0/imm32/alloc-id
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# var old-top/edx = ad->curr
|
|
8b/copy 0/mod/indirect 3/rm32/ebx . . . 2/r32/edx . . # copy *ebx to edx
|
|
# allocate-raw(ad, 2, handle)
|
|
# . . push args
|
|
51/push-ecx
|
|
68/push 2/imm32/size
|
|
53/push-ebx
|
|
# . . call
|
|
e8/call allocate-raw/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# eax = lookup(handle)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 1/rm32/ecx . . . . 4/disp8 . # push *(ecx+4)
|
|
ff 6/subop/push 0/mod/indirect 1/rm32/ecx . . . . . . # push *ecx
|
|
# . . call
|
|
e8/call lookup/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# eax contains old top of heap, except skipping the alloc-id in the payload
|
|
# . check-ints-equal(eax, old-top+4, msg)
|
|
# . . push args
|
|
68/push "F - test-lookup-success"/imm32
|
|
81 0/subop/add 3/mod/direct 2/rm32/edx . . . . . 4/imm32 # add to edx
|
|
52/push-edx
|
|
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
|
|
# clean up
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x100/imm32 # copy to *Next-alloc-id
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
test-lookup-null-returns-null:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var handle/ecx: handle
|
|
68/push 0/imm32/address
|
|
68/push 0/imm32/alloc-id
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# eax = lookup(handle)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 1/rm32/ecx . . . . 4/disp8 . # push *(ecx+4)
|
|
ff 6/subop/push 0/mod/indirect 1/rm32/ecx . . . . . . # push *ecx
|
|
# . . call
|
|
e8/call lookup/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# check-ints-equal(eax, 0, msg)
|
|
# . . push args
|
|
68/push "F - test-lookup-null-returns-null"/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
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
_pending-test-lookup-failure:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var heap/esi: allocation-descriptor
|
|
68/push 0/imm32/limit
|
|
68/push 0/imm32/curr
|
|
89/copy 3/mod/direct 6/rm32/esi . . . 4/r32/esp . . # copy esp to esi
|
|
# heap = new-segment(512)
|
|
# . . push args
|
|
56/push-esi
|
|
68/push 0x200/imm32
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# var h1/ecx: handle
|
|
68/push 0/imm32/address
|
|
68/push 0/imm32/alloc-id
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# var old_top/ebx = heap->curr
|
|
8b/copy 0/mod/indirect 6/rm32/esi . . . 3/r32/ebx . . # copy *esi to ebx
|
|
# first allocation, to h1
|
|
# . allocate(heap, 2, h1)
|
|
# . . push args
|
|
51/push-ecx
|
|
68/push 2/imm32/size
|
|
56/push-esi
|
|
# . . call
|
|
e8/call allocate/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# reset heap->curr to mimic reclamation
|
|
89/copy 0/mod/indirect 6/rm32/esi . . . 3/r32/ebx . . # copy ebx to *esi
|
|
# second allocation that returns the same address as the first
|
|
# var h2/edx: handle
|
|
68/push 0/imm32/address
|
|
68/push 0/imm32/alloc-id
|
|
89/copy 3/mod/direct 2/rm32/edx . . . 4/r32/esp . . # copy esp to edx
|
|
# . allocate(heap, 2, h2)
|
|
# . . push args
|
|
52/push-edx
|
|
68/push 2/imm32/size
|
|
56/push-esi
|
|
# . . call
|
|
e8/call allocate/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# check-ints-equal(h1->address, h2->address, msg)
|
|
# . . push args
|
|
68/push "F - test-lookup-failure"/imm32
|
|
ff 6/subop/push 1/mod/*+disp8 2/rm32/ecx . . . . 4/disp8 . # push *(edx+4)
|
|
ff 6/subop/push 1/mod/*+disp8 1/rm32/ecx . . . . 4/disp8 . # push *(ecx+4)
|
|
# . . call
|
|
e8/call check-ints-equal/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# lookup(h1) should crash
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 1/rm32/ecx . . . . 4/disp8 . # push *(ecx+4)
|
|
ff 6/subop/push 0/mod/indirect 1/rm32/ecx . . . . . . # push *ecx
|
|
# . . call
|
|
e8/call lookup/disp32
|
|
# should never get past this point
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# clean up
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x100/imm32 # copy to *Next-alloc-id
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
# when comparing handles, just treat them as pure values
|
|
handle-equal?: # a: (handle _T), b: (handle _T) -> result/eax: boolean
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
51/push-ecx
|
|
# eax = false
|
|
b8/copy-to-eax 0/imm32/false
|
|
$handle-equal?:compare-alloc-id:
|
|
# ecx = a->alloc_id
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 8/disp8 . # copy *(ebp+8) to ecx
|
|
# if (ecx != b->alloc_id) return false
|
|
39/compare 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0x10/disp8 . # compare ecx and *(ebp+16)
|
|
75/jump-if-!= $handle-equal?:end/disp8
|
|
$handle-equal?:compare-address:
|
|
# ecx = handle->address
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0xc/disp8 . # copy *(ebp+12) to ecx
|
|
# if (ecx != b->address) return false
|
|
39/compare 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0x14/disp8 . # compare ecx and *(ebp+20)
|
|
75/jump-if-!= $handle-equal?:end/disp8
|
|
$handle-equal?:return-true:
|
|
# return true
|
|
b8/copy-to-eax 1/imm32/true
|
|
$handle-equal?:end:
|
|
# . restore registers
|
|
59/pop-to-ecx
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
copy-handle: # src: (handle _T), dest: (addr handle _T)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
# ecx = dest
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0x10/disp8 . # copy *(ebp+16) to ecx
|
|
# *dest = src
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 8/disp8 . # copy *(ebp+8) to eax
|
|
89/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy eax to *ecx
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0xc/disp8 . # copy *(ebp+12) to eax
|
|
89/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy eax to *(ecx+4)
|
|
$copy-handle:end:
|
|
# . restore registers
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
# helper: create a nested allocation descriptor (useful for tests)
|
|
allocate-region: # ad: (addr allocation-descriptor), n: int, out: (addr handle allocation-descriptor)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
# allocate(ad, n, out)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x10/disp8 . # push *(ebp+16)
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
|
|
# . . call
|
|
e8/call allocate/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# eax = out->payload
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0x10/disp8 . # copy *(ebp+16) to eax
|
|
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
|
|
# skip payload->allocid
|
|
05/add-to-eax 4/imm32
|
|
# if (eax == 0) abort
|
|
3d/compare-eax-and 0/imm32
|
|
74/jump-if-= $allocate-region:abort/disp8
|
|
# earmark 8 bytes at the start for a new allocation descriptor
|
|
# . *eax = eax + 8
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 0/r32/eax . . # copy eax to ecx
|
|
81 0/subop/add 3/mod/direct 1/rm32/ecx . . . . . 8/imm32 # add to ecx
|
|
89/copy 0/mod/indirect 0/rm32/eax . . . 1/r32/ecx . . # copy ecx to *eax
|
|
# . *(eax+4) = eax + n
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 0/r32/eax . . # copy eax to ecx
|
|
03/add 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0xc/disp8 . # add *(ebp+12) to ecx
|
|
89/copy 1/mod/*+disp8 0/rm32/eax . . . 1/r32/ecx 4/disp8 . # copy ecx to *(eax+4)
|
|
# . restore registers
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
# We could create a more general '$abort' jump target, but then we'd need to do
|
|
# a conditional jump followed by loading the error message and an unconditional
|
|
# jump. Or we'd need to unconditionally load the error message before a
|
|
# conditional jump, even if it's unused the vast majority of the time. This way
|
|
# we bloat a potentially cold segment in RAM so we can abort with a single
|
|
# instruction.
|
|
$allocate-region:abort:
|
|
# . _write(2/stderr, error)
|
|
# . . push args
|
|
68/push "allocate-region: failed to allocate\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
|
|
e8/call syscall_exit/disp32
|
|
# never gets here
|
|
|
|
# Claim the next 'n+4' bytes of memory and initialize the first 4 to n.
|
|
# Abort if there isn't enough memory in 'ad'.
|
|
allocate-array: # ad: (addr allocation-descriptor), n: int, out: (addr handle _)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
52/push-edx
|
|
# ecx = n
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 1/r32/ecx 0xc/disp8 . # copy *(ebp+12) to ecx
|
|
# var size/edx: int = n+4
|
|
8d/copy-address 1/mod/*+disp8 1/rm32/ecx . . . 2/r32/edx 4/disp8 . # copy ecx+4 to edx
|
|
# allocate(ad, size, out)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x10/disp8 . # push *(ebp+16)
|
|
52/push-edx
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
|
|
# . . call
|
|
e8/call allocate/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# *out->payload = n
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0x10/disp8 . # copy *(ebp+16) to eax
|
|
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
|
|
# . skip payload->allocid
|
|
05/add-to-eax 4/imm32
|
|
# .
|
|
89/copy 0/mod/indirect 0/rm32/eax . . . 1/r32/ecx . . # copy ecx to *eax
|
|
$allocate-array:end:
|
|
# . restore registers
|
|
5a/pop-to-edx
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
test-allocate-array:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var ad/ecx: allocation-descriptor
|
|
68/push 0/imm32/limit
|
|
68/push 0/imm32/curr
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# ad = new-segment(512)
|
|
# . . push args
|
|
51/push-ecx
|
|
68/push 0x200/imm32
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# var expected-payload/ebx = ad->curr
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 3/r32/ebx . . # copy *ecx to ebx
|
|
# var h/edx: handle = {0, 0}
|
|
68/push 0/imm32
|
|
68/push 0/imm32
|
|
89/copy 3/mod/direct 2/rm32/edx . . . 4/r32/esp . . # copy esp to edx
|
|
# *Next-alloc-id = 0x34
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x34/imm32 # copy to *Next-alloc-id
|
|
# allocate-array(ad, 3, h)
|
|
# . . push args
|
|
52/push-edx
|
|
68/push 3/imm32
|
|
51/push-ecx
|
|
# . . call
|
|
e8/call allocate-array/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# check-ints-equal(h->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: sets alloc-id in handle"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 2/rm32/edx . . . . . . # push *edx
|
|
# . . 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(h->payload, expected-payload, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: sets payload in handle"/imm32
|
|
53/push-ebx
|
|
ff 6/subop/push 1/mod/*+disp8 2/rm32/edx . . . . 4/disp8 . # push *(edx+4)
|
|
# . . 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(h->payload->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: sets alloc-id in payload"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 3/rm32/ebx . . . . . . # push *ebx
|
|
# . . 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(h->payload->size, 3, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: sets array size in payload"/imm32
|
|
68/push 3/imm32
|
|
ff 6/subop/push 1/mod/*+disp8 3/rm32/ebx . . . . 4/disp8 . # push *(ebx+4)
|
|
# . . 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(*Next-alloc-id, 0x35, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: increments Next-alloc-id"/imm32
|
|
68/push 0x35/imm32
|
|
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 # push *Next-alloc-id
|
|
# . . 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(ad->curr - expected-payload, 3 + 4 for alloc-id + 4 for array size, msg)
|
|
# . . push args
|
|
68/push "F - test-allocate-array: updates allocation descriptor"/imm32
|
|
68/push 0xb/imm32
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
|
|
29/subtract 3/mod/direct 0/rm32/eax . . . 3/r32/ebx . . # subtract ebx 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
|
|
# clean up
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 1/imm32 # copy to *Next-alloc-id
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
copy-array: # ad: (addr allocation-descriptor), src: (addr array _T), out: (addr handle array _T)
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
52/push-edx
|
|
56/push-esi
|
|
# esi = src
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 0xc/disp8 . # copy *(ebp+12) to esi
|
|
# var size/ecx: int = src->size+4
|
|
8b/copy 0/mod/indirect 6/rm32/esi . . . 1/r32/ecx . . # copy *esi to ecx
|
|
81 0/subop/add 3/mod/direct 1/rm32/ecx . . . . . 4/imm32 # add to ecx
|
|
# allocate(ad, size, out)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x10/disp8 . # push *(ebp+16)
|
|
51/push-ecx
|
|
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
|
|
# . . call
|
|
e8/call allocate/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# var payload/eax: (addr byte) = out->payload
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0x10/disp8 . # copy *(ebp+16) to eax
|
|
8b/copy 1/mod/*+disp8 0/rm32/eax . . . 0/r32/eax 4/disp8 . # copy *(eax+4) to eax
|
|
# . skip payload->allocid
|
|
05/add-to-eax 4/imm32
|
|
# var max/ecx: (addr byte) = payload + size
|
|
01/add 3/mod/direct 1/rm32/ecx . . . 0/r32/eax . . # add eax to ecx
|
|
# _append-4(payload, max, src, &src->data[src->size])
|
|
# . . push &src->data[src->size]
|
|
8b/copy 0/mod/indirect 6/rm32/esi . . . 2/r32/edx . . # copy *esi to edx
|
|
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 2/index/edx . 2/r32/edx 4/disp8 . # copy esi+edx+4 to edx
|
|
52/push-edx
|
|
# . . push src
|
|
56/push-esi
|
|
# . . push max
|
|
51/push-ecx
|
|
# . . push payload
|
|
50/push-eax
|
|
# . . call
|
|
e8/call _append-4/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0x10/imm32 # add to esp
|
|
$copy-array:end:
|
|
# . restore registers
|
|
5e/pop-to-esi
|
|
5a/pop-to-edx
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
test-copy-array:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# var src/esi: (addr array int) = [3, 4, 5]
|
|
68/push 5/imm32
|
|
68/push 4/imm32
|
|
68/push 3/imm32
|
|
68/push 0xc/imm32/size
|
|
89/copy 3/mod/direct 6/rm32/esi . . . 4/r32/esp . . # copy esp to esi
|
|
# var ad/ecx: allocation-descriptor
|
|
68/push 0/imm32/limit
|
|
68/push 0/imm32/curr
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# ad = new-segment(512)
|
|
# . . push args
|
|
51/push-ecx
|
|
68/push 0x200/imm32
|
|
# . . call
|
|
e8/call new-segment/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# var expected-payload/ebx = ad->curr
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 3/r32/ebx . . # copy *ecx to ebx
|
|
# var h/edx: handle = {0, 0}
|
|
68/push 0/imm32
|
|
68/push 0/imm32
|
|
89/copy 3/mod/direct 2/rm32/edx . . . 4/r32/esp . . # copy esp to edx
|
|
# *Next-alloc-id = 0x34
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 0x34/imm32 # copy to *Next-alloc-id
|
|
# copy-array(ad, src, h)
|
|
# . . push args
|
|
52/push-edx
|
|
56/push-esi
|
|
51/push-ecx
|
|
# . . call
|
|
e8/call copy-array/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# check-ints-equal(h->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: sets alloc-id in handle"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 2/rm32/edx . . . . . . # push *edx
|
|
# . . 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(h->payload, expected-payload, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: sets payload in handle"/imm32
|
|
53/push-ebx
|
|
ff 6/subop/push 1/mod/*+disp8 2/rm32/edx . . . . 4/disp8 . # push *(edx+4)
|
|
# . . 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(h->payload->alloc-id, 0x34, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: sets alloc-id in payload"/imm32
|
|
68/push 0x34/imm32
|
|
ff 6/subop/push 0/mod/indirect 2/rm32/edx . . . . . . # push *edx
|
|
# . . call
|
|
e8/call check-ints-equal/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
|
|
# var payload/eax: (addr int) = lookup(h)
|
|
# . . push args
|
|
ff 6/subop/push 1/mod/*+disp8 2/rm32/edx . . . . 4/disp8 . # push *(edx+4)
|
|
ff 6/subop/push 0/mod/indirect 2/rm32/edx . . . . . . # push *edx
|
|
# . . call
|
|
e8/call lookup/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# check-ints-equal(payload->size, 0xc, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: sets array size in payload"/imm32
|
|
68/push 0xc/imm32
|
|
ff 6/subop/push 0/mod/indirect 0/rm32/eax . . . . . . # 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(*Next-alloc-id, 0x35, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: increments Next-alloc-id"/imm32
|
|
68/push 0x35/imm32
|
|
ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 # push *Next-alloc-id
|
|
# . . 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(ad->curr - expected-payload, 12 + 4 for alloc-id + 4 for size, msg)
|
|
# . . push args
|
|
68/push "F - test-copy-array: updates allocation descriptor"/imm32
|
|
68/push 0x14/imm32
|
|
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
|
|
29/subtract 3/mod/direct 0/rm32/eax . . . 3/r32/ebx . . # subtract ebx 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
|
|
# clean up
|
|
c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . Next-alloc-id/disp32 1/imm32 # copy to *Next-alloc-id
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
# Fill a region of memory with zeroes.
|
|
zero-out: # start: (addr byte), size: int
|
|
# pseudocode:
|
|
# curr/esi = start
|
|
# i/ecx = 0
|
|
# while true
|
|
# if (i >= size) break
|
|
# *curr = 0
|
|
# ++curr
|
|
# ++i
|
|
#
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# . save registers
|
|
50/push-eax
|
|
51/push-ecx
|
|
52/push-edx
|
|
56/push-esi
|
|
# curr/esi = start
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 8/disp8 . # copy *(ebp+8) to esi
|
|
# var i/ecx: int = 0
|
|
31/xor 3/mod/direct 1/rm32/ecx . . . 1/r32/ecx . . # clear ecx
|
|
# edx = size
|
|
8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 2/r32/edx 0xc/disp8 . # copy *(ebp+12) to edx
|
|
$zero-out:loop:
|
|
# if (i >= size) break
|
|
39/compare 3/mod/direct 1/rm32/ecx . . . 2/r32/edx . . # compare ecx with edx
|
|
7d/jump-if->= $zero-out:end/disp8
|
|
# *curr = 0
|
|
c6 0/subop/copy 0/mod/direct 6/rm32/esi . . . . . 0/imm8 # copy byte to *esi
|
|
# ++curr
|
|
46/increment-esi
|
|
# ++i
|
|
41/increment-ecx
|
|
eb/jump $zero-out:loop/disp8
|
|
$zero-out:end:
|
|
# . restore registers
|
|
5e/pop-to-esi
|
|
5a/pop-to-edx
|
|
59/pop-to-ecx
|
|
58/pop-to-eax
|
|
# . epilogue
|
|
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
|
|
5d/pop-to-ebp
|
|
c3/return
|
|
|
|
test-zero-out:
|
|
# . prologue
|
|
55/push-ebp
|
|
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
|
|
# region/ecx = 34, 35, 36, 37
|
|
68/push 0x37363534/imm32
|
|
89/copy 3/mod/direct 1/rm32/ecx . . . 4/r32/esp . . # copy esp to ecx
|
|
# zero-out(ecx, 3)
|
|
# . . push args
|
|
68/push 3/imm32/size
|
|
51/push-ecx
|
|
# . . call
|
|
e8/call zero-out/disp32
|
|
# . . discard args
|
|
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
|
|
# first 3 bytes cleared, fourth left alone
|
|
# . check-ints-equal(*ecx, 0x37000000, msg)
|
|
# . . push args
|
|
68/push "F - test-zero-out"/imm32
|
|
68/push 0x37000000/imm32
|
|
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
|
|
# . epilogue
|
|
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
|