From 726b0182beb69954b1429c48a3c20173ba09d3f0 Mon Sep 17 00:00:00 2001
From: AreaZeroArven <122058867+AreaZeroArven@users.noreply.github.com>
Date: Fri, 3 Nov 2023 17:03:43 -0400
Subject: [PATCH 1/2] Have Pokeemerald use OFast, aapcs, and ftoplevel-reorder
 for MODERN by default

The big question is: why make these changes?

Let's take a look:
OFast is a compiler flag that allows for some standard-breaking optimizations, mostly in the floating point category. Pokeemerald rarely uses floating points and where it does, it does not require extreme accuracy. In addition, OFast optimizes for speed, not space, of which there is always 32 MB of anyway.

AAPCS is the ABI that supports arm7tdmi chips and up. It mostly mandated how functions start and end in order to interwork with thumb code. apcs-gnu was back when pokeemerald was still being decompiled.

Finally, ftoplevel-reorder, it is not able to be disabled on clang, and without disabling top-level reordering, the game does not boot. Or rather, it doesn't boot because only one file, m4a.c, does not play nicely with the compiler, causing the game to crash when initializing the sound. For this reason, m4a.c gets its own exception in the Makefile.

These changes should be beneficial to anyone compiling on MODERN and there does not seem to be any downsides. These changes were thoroughly tested for weeks on my end, to ensure no side effects happened. I hope you enjoy this!

Signed-off-by: Arven
---
 Makefile | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 5c073b36ca18..33fe720cb26f 100644
--- a/Makefile
+++ b/Makefile
@@ -107,7 +107,7 @@ LIBPATH := -L ../../tools/agbcc/lib
 LIB := $(LIBPATH) -lgcc -lc -L../../libagbsyscall -lagbsyscall
 else
 CC1              = $(shell $(PATH_MODERNCC) --print-prog-name=cc1) -quiet
-override CFLAGS += -mthumb -mthumb-interwork -O2 -mabi=apcs-gnu -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+override CFLAGS += -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -Wno-pointer-to-int-cast
 ROM := $(MODERN_ROM_NAME)
 OBJ_DIR := $(MODERN_OBJ_DIR_NAME)
 LIBPATH := -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libgcc.a))" -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libnosys.a))" -L "$(dir $(shell $(PATH_MODERNCC) -mthumb -print-file-name=libc.a))"
@@ -297,7 +297,9 @@ $(C_BUILDDIR)/record_mixing.o: CFLAGS += -ffreestanding
 $(C_BUILDDIR)/librfu_intr.o: CC1 := tools/agbcc/bin/agbcc_arm$(EXE)
 $(C_BUILDDIR)/librfu_intr.o: CFLAGS := -O2 -mthumb-interwork -quiet
 else
-$(C_BUILDDIR)/librfu_intr.o: CFLAGS := -mthumb-interwork -O2 -mabi=apcs-gnu -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+$(C_BUILDDIR)/librfu_intr.o: CFLAGS := -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+$(C_BUILDDIR)/m4a.o: CFLAGS := -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
+
 endif
 
 ifeq ($(DINFO),1)

From 5cdda84a451a4a740c5348f5be0f7b8f4a14a404 Mon Sep 17 00:00:00 2001
From: AreaZeroArven <122058867+AreaZeroArven@users.noreply.github.com>
Date: Sat, 11 Nov 2023 14:15:15 -0500
Subject: [PATCH 2/2] Added agb_flash

This file also relies on function ordering to operate properly, even though as of this moment, GCC happens to not do that.
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 33fe720cb26f..71d31e20238c 100644
--- a/Makefile
+++ b/Makefile
@@ -299,7 +299,7 @@ $(C_BUILDDIR)/librfu_intr.o: CFLAGS := -O2 -mthumb-interwork -quiet
 else
 $(C_BUILDDIR)/librfu_intr.o: CFLAGS := -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
 $(C_BUILDDIR)/m4a.o: CFLAGS := -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
-
+$(C_BUILDDIR)/agb_flash.o: CFLAGS := -mthumb -mthumb-interwork -Ofast -mabi=aapcs -mtune=arm7tdmi -march=armv4t -fno-toplevel-reorder -Wno-pointer-to-int-cast
 endif
 
 ifeq ($(DINFO),1)