internal.md

y_cgen - v1.0

Reserve space in COD for newly generated code.

(c) 2022 YSI contibutors, licensed under MPL 1.1

Functions

@_y_cgen0_y_@:

Syntax

@_y_cgen0_y_@()

Remarks

Calls the CGEN() function a massive number of times, to generate a lot of useless assembly whose space we can reuse for useful code (i.e. y_hooks stubs).

Depends on

• CGEN

Attributes

• public

Estimated stack usage

55 cells

@_y_cgen1_y_@:

Syntax

@_y_cgen1_y_@()

Remarks

Denotes the end of the unused code block, so very much relies on the compiler placing this function directly after @_y_cgen0_y_@.

Attributes

• public

Estimated stack usage

1 cells

CGEN:

Syntax

CGEN(&a, &b, &c, &d, &e, &f, &g, &h, &i, &j, &k, &l, &m, &n, &o, &p, &q, &r, &s, &t, &u, &v, &w, &x, &y, &z)

Parameters

Name	Info
a	&
b	&
c	&
d	&
e	&
f	&
g	&
h	&
i	&
j	&
k	&
l	&
m	&
n	&
o	&
p	&
q	&
r	&
s	&
t	&
u	&
v	&
w	&
x	&
y	&
z	&

Returns

Remarks

This is just a function that takes very little pawn code, but an awful lot of p-code, to call. The pawn is just CGEN(), but thanks to having a huge number of reference parameters all with default constant values the generated assembly is massive, with twenty-six heap allocations and pushes. It doesn't even do anything, just reserves a huge block of code space in which we can generate new code.

Estimated stack usage

1 cells

CGen_GetAddr:

Syntax

CGen_GetAddr(func[])

Parameters

Name	Info
func	[] Function name to get the address of.

Returns

The address of the function.

Remarks

Why this doesn't use functions from in y_amx I don't know.

Depends on

• AMX_HEADER_COD
• AMX_HEADER_PUBLICS
• YSI_gAMXAddress_
• __defsize_cells
• funcidx

Estimated stack usage

3 cells

CGen_OOM:

Syntax

CGen_OOM(ctx[])

Parameters

Name	Info
ctx	[21] The AsmContext that ran out of space.

Remarks

Called by amx_assembly when more code is written than there is space for, or on some other errors.

Depends on

• ASM_ERROR_LABEL_DUPLICATE
• ASM_ERROR_LABEL_OVERFLOW
• ASM_ERROR_NONE
• ASM_ERROR_OPCODE
• ASM_ERROR_OPERAND
• ASM_ERROR_SPACE
• AsmClearError
• AsmGetError
• Debug_Kill_
• Debug_Print0

Attributes

• public

Estimated stack usage

8 cells

CGen_SetupCodeSpace:

Syntax

CGen_SetupCodeSpace()

Remarks

Initialises the storage for unused code, and ensures that the functions being clobbered by said code are at least left in a semi-valid state.

Depends on

• CGen_GetAddr
• OP_PROC
• OP_RETN
• OP_ZERO_PRI
• RelocateOpcode
• YSI_gAMXAddress_
• YSI_g_sCodeEnd
• YSI_g_sCodeSpace
• __1_cell
• __2_cells
• __3_cells

Estimated stack usage

4 cells

VA_OnCodeInit:

Syntax

VA_OnCodeInit()

Remarks

Initialise the library.

Depends on

• AMX_HEADER_COD
• CGen_SetupCodeSpace
• DisasmContext
• DisasmInit
• DisasmNextInsn
• OP_NONE
• OP_NOP
• RelocateOpcode
• YSI_gAMXAddress_
• YSI_g_sCodeSpace

Attributes

• public

Estimated stack usage

11 cells