support checking overflow flag everywhere

This commit is contained in:
Kartik K. Agaram 2021-05-08 21:16:23 -07:00
parent df68e6eddc
commit f9f419af71
8 changed files with 517 additions and 9 deletions

View File

@ -405,3 +405,27 @@ void test_jle_disp8_greater() {
);
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
}
//:: jump if overflow
:(before "End Initialize Op Names")
put_new(Name, "70", "jump disp8 bytes away if OF is set (jcc/jo)");
put_new(Name, "71", "jump disp8 bytes away if OF is unset (jcc/jno)");
:(before "End Single-Byte Opcodes")
case 0x70: { // jump disp8 if OF is set
const int8_t offset = static_cast<int>(next());
if (OF) {
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
case 0x71: { // jump disp8 if OF is unset
const int8_t offset = static_cast<int>(next());
if (!OF) {
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}

View File

@ -405,3 +405,27 @@ void test_jle_disp32_greater() {
);
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
}
//:: jump if overflow
:(before "End Initialize Op Names")
put_new(Name_0f, "80", "jump disp32 bytes away if OF is set (jcc/jo)");
put_new(Name_0f, "81", "jump disp32 bytes away if OF is unset (jcc/jno)");
:(before "End Two-Byte Opcodes Starting With 0f")
case 0x80: { // jump disp8 if OF is set
const int32_t offset = next32();
if (OF) {
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
case 0x81: { // jump disp8 if OF is unset
const int32_t offset = next32();
if (!OF) {
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}

40
linux/branches.mu Normal file
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@ -0,0 +1,40 @@
fn foo {
$foo: {
break-if-=
break-if-= $foo
break-if-!=
break-if-!= $foo
break-if-<=
break-if-<= $foo
break-if->=
break-if->= $foo
break-if-<
break-if-< $foo
break-if->
break-if-> $foo
break-if-carry
break-if-carry $foo
break-if-overflow
break-if-overflow $foo
loop-if-=
loop-if-= $foo
loop-if-!=
loop-if-!= $foo
loop-if-<=
loop-if-<= $foo
loop-if->=
loop-if->= $foo
loop-if-<
loop-if-< $foo
loop-if->
loop-if-> $foo
loop-if-carry
loop-if-carry $foo
loop-if-not-carry
loop-if-not-carry $foo
loop-if-overflow
loop-if-overflow $foo
loop-if-not-overflow
loop-if-not-overflow $foo
}
}

161
linux/branches.out Normal file
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@ -0,0 +1,161 @@
== code
foo:
# . prologue
55/push-ebp
89/<- %ebp 4/r32/esp
{
$foo:0x00000001:loop:
{
$foo:loop:
{
0f 85/jump-if-!= break/disp32
e9/jump $foo:break/disp32
}
{
0f 85/jump-if-!= break/disp32
e9/jump $foo:break/disp32
}
{
0f 84/jump-if-= break/disp32
e9/jump $foo:break/disp32
}
{
0f 84/jump-if-= break/disp32
e9/jump $foo:break/disp32
}
{
0f 8f/jump-if-> break/disp32
e9/jump $foo:break/disp32
}
{
0f 8f/jump-if-> break/disp32
e9/jump $foo:break/disp32
}
{
0f 8c/jump-if-< break/disp32
e9/jump $foo:break/disp32
}
{
0f 8c/jump-if-< break/disp32
e9/jump $foo:break/disp32
}
{
0f 8d/jump-if->= break/disp32
e9/jump $foo:break/disp32
}
{
0f 8d/jump-if->= break/disp32
e9/jump $foo:break/disp32
}
{
0f 8e/jump-if-<= break/disp32
e9/jump $foo:break/disp32
}
{
0f 8e/jump-if-<= break/disp32
e9/jump $foo:break/disp32
}
{
0f 83/jump-if-addr>= break/disp32
e9/jump $foo:break/disp32
}
{
0f 83/jump-if-addr>= break/disp32
e9/jump $foo:break/disp32
}
{
0f 81/jump-if-not-overflow break/disp32
e9/jump $foo:break/disp32
}
{
0f 81/jump-if-not-overflow break/disp32
e9/jump $foo:break/disp32
}
{
0f 85/jump-if-!= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 85/jump-if-!= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 84/jump-if-= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 84/jump-if-= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8f/jump-if-> break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8f/jump-if-> break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8c/jump-if-< break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8c/jump-if-< break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8d/jump-if->= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8d/jump-if->= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8e/jump-if-<= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 8e/jump-if-<= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 83/jump-if-addr>= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 83/jump-if-addr>= break/disp32
e9/jump $foo:loop/disp32
}
{
0f 82/jump-if-addr< break/disp32
e9/jump $foo:loop/disp32
}
{
0f 82/jump-if-addr< break/disp32
e9/jump $foo:loop/disp32
}
{
0f 81/jump-if-not-overflow break/disp32
e9/jump $foo:loop/disp32
}
{
0f 81/jump-if-not-overflow break/disp32
e9/jump $foo:loop/disp32
}
{
0f 80/jump-if-overflow break/disp32
e9/jump $foo:loop/disp32
}
{
0f 80/jump-if-overflow break/disp32
e9/jump $foo:loop/disp32
}
}
$foo:break:
}
$foo:0x00000001:break:
# . epilogue
89/<- %esp 5/r32/ebp
5d/pop-to-ebp
c3/return

BIN
linux/mu

Binary file not shown.

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@ -27610,9 +27610,9 @@ $emit-reverse-break:end:
# Table from Mu branch instructions to the reverse SubX opcodes for them.
Reverse-branch: # (table (handle array byte) (handle array byte))
# a table is a stream
0x1c0/imm32/write
0x240/imm32/write
0/imm32/read
0x1c0/imm32/size
0x240/imm32/size
# data
0x11/imm32/alloc-id _string-break-if-=/imm32 0x11/imm32/alloc-id _string_0f_85_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-=/imm32 0x11/imm32/alloc-id _string_0f_85_jump_label/imm32
@ -27642,6 +27642,14 @@ Reverse-branch: # (table (handle array byte) (handle array byte))
0x11/imm32/alloc-id _string-loop-if-float<=/imm32 0x11/imm32/alloc-id _string_0f_87_jump_label/imm32
0x11/imm32/alloc-id _string-break-if-float>=/imm32 0x11/imm32/alloc-id _string_0f_82_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-float>=/imm32 0x11/imm32/alloc-id _string_0f_82_jump_label/imm32
0x11/imm32/alloc-id _string-break-if-carry/imm32 0x11/imm32/alloc-id _string_0f_83_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-carry/imm32 0x11/imm32/alloc-id _string_0f_83_jump_label/imm32
0x11/imm32/alloc-id _string-break-if-not-carry/imm32 0x11/imm32/alloc-id _string_0f_82_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-not-carry/imm32 0x11/imm32/alloc-id _string_0f_82_jump_label/imm32
0x11/imm32/alloc-id _string-break-if-overflow/imm32 0x11/imm32/alloc-id _string_0f_81_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-overflow/imm32 0x11/imm32/alloc-id _string_0f_81_jump_label/imm32
0x11/imm32/alloc-id _string-break-if-not-overflow/imm32 0x11/imm32/alloc-id _string_0f_80_jump_label/imm32
0x11/imm32/alloc-id _string-loop-if-not-overflow/imm32 0x11/imm32/alloc-id _string_0f_80_jump_label/imm32
== code
@ -32836,6 +32844,82 @@ _Primitive-break-if->: # (payload primitive)
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-break-if-carry/imm32/next
_Primitive-break-if-carry: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-break-if-carry/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_82_jump_break/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-break-if-not-carry/imm32/next
_Primitive-break-if-not-carry: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-break-if-not-carry/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_83_jump_break/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-break-if-overflow/imm32/next
_Primitive-break-if-overflow: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-break-if-overflow/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_80_jump_break/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-break-if-not-overflow/imm32/next
_Primitive-break-if-not-overflow: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-break-if-not-overflow/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_81_jump_break/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-break/imm32/next
_Primitive-break: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
@ -33045,6 +33129,82 @@ _Primitive-loop-if->: # (payload primitive)
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-loop-if-carry/imm32/next
_Primitive-loop-if-carry: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-loop-if-carry/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_82_jump_loop/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-loop-if-not-carry/imm32/next
_Primitive-loop-if-not-carry: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-loop-if-not-carry/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_83_jump_loop/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-loop-if-overflow/imm32/next
_Primitive-loop-if-overflow: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-loop-if-overflow/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_80_jump_loop/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-loop-if-not-overflow/imm32/next
_Primitive-loop-if-not-overflow: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
0x11/imm32/alloc-id:fake
_string-loop-if-not-overflow/imm32/name
0/imm32/no-inouts
0/imm32/no-inouts
0/imm32/no-outputs
0/imm32/no-outputs
0x11/imm32/alloc-id:fake
_string_0f_81_jump_loop/imm32/subx-name
0/imm32/no-rm32
0/imm32/no-r32
0/imm32/no-imm32
0/imm32/no-imm8
0/imm32/no-disp32
0/imm32/no-xm32
0/imm32/no-x32
0x11/imm32/alloc-id:fake
_Primitive-loop/imm32/next # we probably don't need an unconditional break
_Primitive-loop: # (payload primitive)
0x11/imm32/alloc-id:fake:payload
@ -33891,6 +34051,26 @@ _string-break-if-float>=: # (payload array byte)
# "break-if-float>="
0x10/imm32/size
0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x66/f 0x6c/l 0x6f/o 0x61/a 0x74/t 0x3e/> 0x3d/=
_string-break-if-carry: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "break-if-carry"
0xe/imm32/size
0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x63/c 0x61/a 0x72/r 0x72/r 0x79/y
_string-break-if-not-carry: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "break-if-not-carry"
0x12/imm32/size
0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x63/c 0x61/a 0x72/r 0x72/r 0x79/y
_string-break-if-overflow: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "break-if-overflow"
0x11/imm32/size
0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string-break-if-not-overflow: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "break-if-not-overflow"
0x15/imm32/size
0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string-compare: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "compare"
@ -33910,12 +34090,12 @@ _string-copy-byte:
0x11/imm32/alloc-id:fake:payload
# "copy-byte"
0x9/imm32/size
0x63/c 0x6f/o 0x70/p 0x79/y 0x2d/- 0x62/b 0x79/y 0x74/t 0x65/e
0x63/c 0x6f/o 0x70/p 0x79/y 0x2d/dash 0x62/b 0x79/y 0x74/t 0x65/e
_string-copy-byte-to:
0x11/imm32/alloc-id:fake:payload
# "copy-byte-to"
0xc/imm32/size
0x63/c 0x6f/o 0x70/p 0x79/y 0x2d/- 0x62/b 0x79/y 0x74/t 0x65/e 0x2d/- 0x74/t 0x6f/o
0x63/c 0x6f/o 0x70/p 0x79/y 0x2d/dash 0x62/b 0x79/y 0x74/t 0x65/e 0x2d/dash 0x74/t 0x6f/o
_string-decrement: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "decrement"
@ -34001,6 +34181,26 @@ _string-loop-if-float>=: # (payload array byte)
# "loop-if-float>="
0xf/imm32/size
0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x66/f 0x6c/l 0x6f/o 0x61/a 0x74/t 0x3e/> 0x3d/=
_string-loop-if-carry: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "loop-if-carry"
0xd/imm32/size
0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x63/c 0x61/a 0x72/r 0x72/r 0x79/y
_string-loop-if-not-carry: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "loop-if-not-carry"
0x11/imm32/size
0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x63/c 0x61/a 0x72/r 0x72/r 0x79/y
_string-loop-if-overflow: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "loop-if-overflow"
0x10/imm32/size
0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string-loop-if-not-overflow: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "loop-if-not-overflow"
0x14/imm32/size
0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string-multiply: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "multiply"
@ -34045,12 +34245,12 @@ _string-square-root:
0x11/imm32/alloc-id:fake:payload
# "square-root"
0xb/imm32/size
0x73/s 0x71/q 0x75/u 0x61/a 0x72/r 0x65/e 0x2d/- 0x72/r 0x6f/o 0x6f/o 0x74/t
0x73/s 0x71/q 0x75/u 0x61/a 0x72/r 0x65/e 0x2d/dash 0x72/r 0x6f/o 0x6f/o 0x74/t
_string-inverse-square-root:
0x11/imm32/alloc-id:fake:payload
# "inverse-square-root"
0x13/imm32/size
0x69/i 0x6e/n 0x76/v 0x65/e 0x72/r 0x73/s 0x65/e 0x2d/- 0x73/s 0x71/q 0x75/u 0x61/a 0x72/r 0x65/e 0x2d/- 0x72/r 0x6f/o 0x6f/o 0x74/t
0x69/i 0x6e/n 0x76/v 0x65/e 0x72/r 0x73/s 0x65/e 0x2d/dash 0x73/s 0x71/q 0x75/u 0x61/a 0x72/r 0x65/e 0x2d/dash 0x72/r 0x6f/o 0x6f/o 0x74/t
_string-negate: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "negate"
@ -34133,6 +34333,36 @@ _string_0d_or_with_eax: # (payload array byte)
# "0d/or-with-eax"
0xe/imm32/size
0x30/0 0x64/d 0x2f/slash 0x6f/o 0x72/r 0x2d/dash 0x77/w 0x69/i 0x74/t 0x68/h 0x2d/dash 0x65/e 0x61/a 0x78/x
_string_0f_80_jump_label: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 80/jump-if-overflow"
0x16/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x30/0 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string_0f_80_jump_break: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 80/jump-if-overflow break/disp32"
0x23/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x30/0 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w 0x20/space 0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2f/slash 0x64/d 0x69/i 0x73/s 0x70/p 0x33/3 0x32/2
_string_0f_80_jump_loop: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 80/jump-if-overflow loop/disp32"
0x22/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x30/0 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w 0x20/space 0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2f/slash 0x64/d 0x69/i 0x73/s 0x70/p 0x33/3 0x32/2
_string_0f_81_jump_label: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 81/jump-if-not-overflow"
0x1a/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x31/1 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w
_string_0f_81_jump_break: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 81/jump-if-not-overflow break/disp32"
0x27/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x31/1 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w 0x20/space 0x62/b 0x72/r 0x65/e 0x61/a 0x6b/k 0x2f/slash 0x64/d 0x69/i 0x73/s 0x70/p 0x33/3 0x32/2
_string_0f_81_jump_loop: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 81/jump-if-not-overflow loop/disp32"
0x26/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x31/1 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x6e/n 0x6f/o 0x74/t 0x2d/dash 0x6f/o 0x76/v 0x65/e 0x72/r 0x66/f 0x6c/l 0x6f/o 0x77/w 0x20/space 0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2f/slash 0x64/d 0x69/i 0x73/s 0x70/p 0x33/3 0x32/2
_string_0f_82_jump_label: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 82/jump-if-addr<"
@ -34176,7 +34406,7 @@ _string_0f_84_jump_break: # (payload array byte)
_string_0f_84_jump_loop: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "0f 84/jump-if-= loop/disp32"
0x1b/imm32/size
0x1a/imm32/size
0x30/0 0x66/f 0x20/space 0x38/8 0x34/4 0x2f/slash 0x6a/j 0x75/u 0x6d/m 0x70/p 0x2d/dash 0x69/i 0x66/f 0x2d/dash 0x3d/= 0x6c/l 0x6f/o 0x6f/o 0x70/p 0x2f/slash 0x64/d 0x69/i 0x73/s 0x70/p 0x33/3 0x32/2
_string_0f_85_jump_label: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
@ -34527,12 +34757,12 @@ _string_8a_copy_byte:
0x11/imm32/alloc-id:fake:payload
# "8a/byte->"
0x9/imm32/size
0x38/8 0x61/a 0x2f// 0x62/b 0x79/y 0x74/t 0x65/e 0x2d/- 0x3e/>
0x38/8 0x61/a 0x2f/slash 0x62/b 0x79/y 0x74/t 0x65/e 0x2d/dash 0x3e/>
_string_88_copy_byte:
0x11/imm32/alloc-id:fake:payload
# "88/byte<-"
0x9/imm32/size
0x38/8 0x38/8 0x2f// 0x62/b 0x79/y 0x74/t 0x65/e 0x3c/< 0x2d/-
0x38/8 0x38/8 0x2f/slash 0x62/b 0x79/y 0x74/t 0x65/e 0x3c/< 0x2d/-
_string_8d_copy_address: # (payload array byte)
0x11/imm32/alloc-id:fake:payload
# "8d/copy-address"

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@ -293,6 +293,31 @@ Similar float variants like `break-if-float<` are aliases for the corresponding
`addr` equivalents. The x86 instruction set stupidly has floating-point
operations only update a subset of flags.
Four sets of conditional jumps are useful for detecting overflow.
break-if-carry => "0f 82/jump-if-carry break/disp32"
break-if-carry label => "0f 82/jump-if-carry " label "/disp32"
loop-if-carry => "0f 82/jump-if-carry break/disp32"
loop-if-carry label => "0f 82/jump-if-carry " label "/disp32"
break-if-not-carry => "0f 83/jump-if-not-carry break/disp32"
break-if-not-carry label => "0f 83/jump-if-not-carry " label "/disp32"
loop-if-not-carry => "0f 83/jump-if-not-carry break/disp32"
loop-if-not-carry label => "0f 83/jump-if-not-carry " label "/disp32"
break-if-overflow => "0f 80/jump-if-overflow break/disp32"
break-if-overflow label => "0f 80/jump-if-overflow " label ":break/disp32"
loop-if-overflow => "0f 80/jump-if-overflow loop/disp32"
loop-if-overflow label => "0f 80/jump-if-overflow " label ":loop/disp32"
break-if-not-overflow => "0f 81/jump-if-not-overflow break/disp32"
break-if-not-overflow label => "0f 81/jump-if-not-overflow " label ":break/disp32"
loop-if-not-overflow => "0f 81/jump-if-not-overflow loop/disp32"
loop-if-not-overflow label => "0f 81/jump-if-not-overflow " label ":loop/disp32"
All this relies on a convention that every `{}` block is delimited by labels
ending in `:loop` and `:break`.
## Returns
The `return` instruction cleans up variable declarations just like an unconditional

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@ -51,6 +51,8 @@ Opcodes currently supported by SubX:
5f: pop top of stack to EDI (pop)
68: push imm32 to stack (push)
69: multiply rm32 by imm32 and store result in r32 (imul)
70: jump disp8 bytes away if OF is set (jcc/jo)
71: jump disp8 bytes away if OF is unset (jcc/jno)
72: jump disp8 bytes away if lesser (addr, float), if CF is set (jcc/jb/jnae)
73: jump disp8 bytes away if greater or equal (addr, float), if CF is unset (jcc/jae/jnb)
74: jump disp8 bytes away if equal, if ZF is set (jcc/jz/je)
@ -91,6 +93,8 @@ Opcodes currently supported by SubX:
f7: negate/multiply/divide rm32 (with EAX and EDX if necessary) depending on subop (neg/mul/idiv)
ff: increment/decrement/jump/push/call rm32 based on subop (inc/dec/jmp/push/call)
0f 2f: compare: set CF if x32 < xm32 (comiss)
0f 80: jump disp32 bytes away if OF is set (jcc/jo)
0f 81: jump disp32 bytes away if OF is unset (jcc/jno)
0f 82: jump disp32 bytes away if lesser (addr, float), if CF is set (jcc/jb/jnae)
0f 83: jump disp32 bytes away if greater or equal (addr, float), if CF is unset (jcc/jae/jnb)
0f 84: jump disp32 bytes away if equal, if ZF is set (jcc/jz/je)