From c6ec8fa3f77ba24e92ce8fda32b6919f0f67e496 Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Wed, 10 Jul 2019 10:55:30 -0700 Subject: zero out new rows returned by get-or-insert --- subx/076zero-out.subx | 84 +++++++++++++++++++++++++++++++++++++++++++++ subx/apps/assort | Bin 32098 -> 32242 bytes subx/apps/crenshaw2-1 | Bin 23725 -> 23839 bytes subx/apps/crenshaw2-1b | Bin 24284 -> 24398 bytes subx/apps/dquotes | Bin 38451 -> 38595 bytes subx/apps/factorial | Bin 22641 -> 22755 bytes subx/apps/handle | Bin 23500 -> 23614 bytes subx/apps/hex | Bin 26734 -> 26848 bytes subx/apps/pack | Bin 44464 -> 44608 bytes subx/apps/subx-common.subx | 19 ++++++++++ subx/apps/survey | Bin 38602 -> 38746 bytes 11 files changed, 103 insertions(+) create mode 100644 subx/076zero-out.subx (limited to 'subx') diff --git a/subx/076zero-out.subx b/subx/076zero-out.subx new file mode 100644 index 00000000..bc19dc21 --- /dev/null +++ b/subx/076zero-out.subx @@ -0,0 +1,84 @@ +# Fill a region of memory with zeroes. + +== 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 + +zero-out: # start : address, len : int + # pseudocode: + # curr/ESI = start + # i/ECX = 0 + # while true + # if (i >= len) break + # *curr = 0 + # ++curr + # ++i + # + # . prolog + 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 + # i/ECX = 0 + 31/xor 3/mod/direct 1/rm32/ECX . . . 1/r32/ECX . . # clear ECX + # EDX = len + 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX +$zero-out:loop: + # if (i >= len) break + 39/compare 3/mod/direct 1/rm32/ECX . . . 2/r32/EDX . . # compare ECX with EDX + 7d/jump-if-greater-or-equal $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 + # . epilog + 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP + 5d/pop-to-EBP + c3/return + +test-zero-out: + # . prolog + 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/len + 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 + # . 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 diff --git a/subx/apps/assort b/subx/apps/assort index dc437fba..83a063f0 100755 Binary files a/subx/apps/assort and b/subx/apps/assort differ diff --git a/subx/apps/crenshaw2-1 b/subx/apps/crenshaw2-1 index 2dc6e6d4..e5e6560c 100755 Binary files a/subx/apps/crenshaw2-1 and b/subx/apps/crenshaw2-1 differ diff --git a/subx/apps/crenshaw2-1b b/subx/apps/crenshaw2-1b index efa0ece7..eebd667a 100755 Binary files a/subx/apps/crenshaw2-1b and b/subx/apps/crenshaw2-1b differ diff --git a/subx/apps/dquotes b/subx/apps/dquotes index c803fa9e..e982690c 100755 Binary files a/subx/apps/dquotes and b/subx/apps/dquotes differ diff --git a/subx/apps/factorial b/subx/apps/factorial index 2433b2a6..55a59123 100755 Binary files a/subx/apps/factorial and b/subx/apps/factorial differ diff --git a/subx/apps/handle b/subx/apps/handle index d1cbb74b..3ea729c6 100755 Binary files a/subx/apps/handle and b/subx/apps/handle differ diff --git a/subx/apps/hex b/subx/apps/hex index 5bfa5863..315e855c 100755 Binary files a/subx/apps/hex and b/subx/apps/hex differ diff --git a/subx/apps/pack b/subx/apps/pack index 8eff81dd..7ad19415 100755 Binary files a/subx/apps/pack and b/subx/apps/pack differ diff --git a/subx/apps/subx-common.subx b/subx/apps/subx-common.subx index e8b3140c..129c9821 100644 --- a/subx/apps/subx-common.subx +++ b/subx/apps/subx-common.subx @@ -24,6 +24,7 @@ get-or-insert: # table : (address stream {string, _}), key : (address string), # curr += row-size # if table->write >= table->length # abort + # zero-out(max, row-size) # *max = key # table->write += row-size # return max+4 @@ -72,6 +73,14 @@ $get-or-insert:not-found: 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 @@ -258,6 +267,7 @@ $test-get-or-insert:end: # scan 'table' for a row with a key 'key' and return the address of the corresponding value # 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 get-or-insert-slice: # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _) # pseudocode: @@ -269,6 +279,7 @@ get-or-insert-slice: # table : (address stream {string, _}), key : (address sli # 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 @@ -317,6 +328,14 @@ $get-or-insert-slice:not-found: 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 $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 diff --git a/subx/apps/survey b/subx/apps/survey index 9290e1ae..0c900562 100755 Binary files a/subx/apps/survey and b/subx/apps/survey differ -- cgit 1.4.1-2-gfad0