I know that International Hack Release Day is a few months away, but I had a brainwave recently that compelled me to write this. So:
THUMBLIB v3 (DOWNLOAD)
The previous version of THUMBLIB was a library for writing THUMB assembly within Event Assembler source files. This iteration of the concept is for wizards who like to write their code using the C programming language. An example taken from my Repair Items hack rewrite:
#define THUMBLIB_VOLATILE
#include "gbafe.h"
#include "thumblib3.h"
Unit* GetUnitStructFromEventParameter(s16 unitKind);
void RepairItems_Internal(Unit* unit);
THUMBLIB_FUNC void ASMC_RepairItems(Proc* eventEngineProc) {
register unsigned* slots;
register int slotOffset;
register void* call;
register signed unitKind asm("r0");
register Unit* unit asm("r0");
PUSH_LR();
LDR_POOL(slots, &gEventSlot);
MOV_I(slotOffset, sizeof(s16) * 1);
LDSH(unitKind, slots, slotOffset);
LDR_POOL(call, &GetUnitStructFromEventParameter);
MOV_TO_LR(call);
BL_LR();
CMP_I(unit, NULL);
BEQ(_End);
LDR_POOL(call, &RepairItems_Internal);
MOV_TO_LR(call);
BL_LR();
_End:;
POP(call);
BX(call);
}
There are a few things to note here:
The library has a function attribute macro THUMBLIB_FUNC that should be used for functions. It prevents the compiler from generating pushes/pops and other stuff, along with reducing the chance that things will be optimized out.
Before including the library, THUMBLIB_VOLATILE is defined, which marks all THUMBLIB assembly as volatile, further reducing the chance that the compiler will optimize things out.
You should specify the exact registers to use for a variable when they’re the inputs/outputs of a function call. You can leave out the register if it’s not important to use a specific one.
The optimizer/compiler will absolutely be mean and mangle your beautiful assembly, so be sure to check to make sure that anything generated is correct. I am not liable for anything that happens when using this library.