X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?p=fceu.git;a=blobdiff_plain;f=ncpu.S;h=dcade08fabf64a4d74ac9939594561487f078899;hp=0b000ec2bee35102d61c3f610fd40f7909db6ab0;hb=e328100eecae3adfce1c3b57364bee5d166217ef;hpb=0b65fdb3548fd54670265adfb80706e63da6b641

diff --git a/ncpu.S b/ncpu.S
index 0b000ec..dcade08 100644
--- a/ncpu.S
+++ b/ncpu.S
@@ -91,7 +91,7 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@
 @@@ ¤Ê¤ó¤«Ì¾Á°¤¬ÊѤÀ¤Ê(¤É¡¼¤Ç¤â¤¤¡¼¤±¤É¡¼
 @@@
-.macro	CYCLE_NEXT	n, hook_check=1, do_cyc_add=1
+.macro	CYCLE_NEXT	n, unused=0, do_cyc_add=1
 	@@DEBUG_INFO
 
 .if \do_cyc_add
@@ -99,17 +99,17 @@ ldmfd sp!,{r0-r3,r12,lr}
 .endif
 	subs	REG_CYCLE, REG_CYCLE, #\n*48<<16
 	ble	cpu_exec_end
-.if \hook_check
 	tst	REG_P_REST, #1<<16
-	blne	do_irq_hook
-.endif
+	bne	do_irq_hook
+
 	ldrb	r0, [REG_PC], #1
 	tst	REG_P_REST, #0xff<<8
 	ldreq	pc, [REG_OP_TABLE, r0, lsl #2]
 
 	@ do some messing to find out which IRQ is pending..
-	tst	REG_P_REST, #FCEU_IQNMI<<8
-	bne	do_int
+	@ assumption: NMI can be set only on very first run, because it is only set once before vblank..
+@	tst	REG_P_REST, #FCEU_IQNMI<<8
+@	bne	do_int
 	tst	REG_P_REST, #P_REST_I_FLAG
 	@@ if I_FLAG=1, continue execution, don't trigger IRQ
 	bicne	REG_P_REST, REG_P_REST, #FCEU_IQTEMP<<8
@@ -205,20 +205,13 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@ Read byte
 @@@
 
-.macro	READ rom_optimize=1
-	adr	lr, 1f
-.if \rom_optimize
-	tst	REG_ADDR, #0x8000
-	bne	read_rom_byte
-.endif
+.macro	READ unused_param
 	tst	REG_ADDR, #0xe000
-	bne	read_byte
 	@ RAM
-	bic	r0, REG_ADDR, #0x1800
-	add	r0, r0, #OTOFFS_NES_RAM
-	ldrb	r0, [r0, REG_OP_TABLE]
-	@@ ¤È¤¤¤¦¤ï¤±¤Ç¥¸¥ã¥ó¥×¤¹¤ëɬÍפϤʤ¤
-1:
+	biceq	r0, REG_ADDR, #0x1800
+	addeq	r0, r0, #OTOFFS_NES_RAM
+	ldreqb	r0, [r0, REG_OP_TABLE]
+	blne	read_byte
 .endm
 
 @@@
@@ -235,10 +228,8 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@ OP¤Ç¤Ïr3¤òÊݸ¤·¤Ê¤±¤ì¤Ð¤Ê¤é¤Ê¤¤
 
 .macro	READ_WRITE_1
-	adr	lr, 9999f
-	tst	REG_ADDR, #0x8000
-	bne	read_rom_byte
 	tst	REG_ADDR, #0xe000
+	adrne	lr, 9999f
 	bne	read_byte
 	@ RAM
 	bic	REG_ADDR, REG_ADDR, #0x1800
@@ -282,7 +273,6 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@ REG_ADDR¤òÊѹ¹¤¹¤ë¤¬µ¤¤Ë¤¹¤ë¤Ê
 @@@
 .macro	READ_WORD
-	@ don't do ROM check, because we might be fetching important stuff like vectors
 	READ    0
 	mov	REG_PC, r0
 	add	REG_ADDR, REG_ADDR, #1
@@ -415,18 +405,25 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 @@@ $nnnn
 
-.macro	ABS_ADDR
+.macro	ABS_ADDR update_db=0
+.if \update_db
+	ldrb	r0, [REG_PC, #1]
+	ldrb	REG_ADDR, [REG_PC], #2
+	strb    r0, [REG_OP_TABLE, #(OTOFFS_X + 0x10)]		@ X.DB
+	orr	REG_ADDR, REG_ADDR, r0, lsl #8
+.else
 	tst	REG_PC, #1
 	ldrneb	REG_ADDR, [REG_PC], #1
 	ldrneb	r0, [REG_PC], #1
 	ldreqh	REG_ADDR, [REG_PC], #2
 	orrne	REG_ADDR, REG_ADDR, r0, lsl #8
+.endif
 .endm
 
 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 @@@ $nnnn, X
 .macro	ABSX_ADDR
-	ABS_ADDR
+	ABS_ADDR 1
 	add	REG_ADDR, REG_ADDR, REG_X
 	bic	REG_ADDR, REG_ADDR, #0x10000
 	and	r0,REG_ADDR,#0xff
@@ -445,7 +442,7 @@ ldmfd sp!,{r0-r3,r12,lr}
 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 @@@ $nnnn, Y
 .macro	ABSY_ADDR
-	ABS_ADDR
+	ABS_ADDR 1					@ a hack needed for Paperboy, Dirty Harry controls to work
 	add	REG_ADDR, REG_ADDR, REG_Y
 	bic	REG_ADDR, REG_ADDR, #0x10000
 	and	r0,REG_ADDR,#0xff
@@ -2723,10 +2720,11 @@ reset_cpu:
 @@@ low-level memhandlers
 @@@
 
+/*
+@ disabled because no improvements noticed, only causes trouble (with gg for example)
 read_rom_byte:
 @ try to avoid lookup of every address at least for ROM and RAM areas
 @ I've verified that if ARead[0xfff0] points to CartBR, it is always normal ROM read.
-#ifndef DEBUG_ASM_6502
 	ldr	r0, =CartBR
 	ldr	r2, =ARead
 	mov	r1, #0xff00
@@ -2739,7 +2737,7 @@ read_rom_byte:
 	ldr	r2, [r2, r1, lsl #2]
 	ldrb	r0, [r2, REG_ADDR]
 	bx	lr
-#endif
+*/
 
 
 read_byte:
@@ -2835,13 +2833,26 @@ cpu_exec:
 
 @	ldr   REG_OP_TABLE, = cpu_exec_table @ set on init
 
-	CYCLE_NEXT	0, 0
+	ldrb	r0, [REG_PC], #1
+	tst	REG_P_REST, #0xff<<8
+	ldreq	pc, [REG_OP_TABLE, r0, lsl #2]
+
+	@ assumption: NMI can be set only on very first run, because it is only set once before vblank..
+	tst	REG_P_REST, #FCEU_IQNMI<<8
+	bne	do_int
+	tst	REG_P_REST, #P_REST_I_FLAG
+	@@ if I_FLAG=1, continue execution, don't trigger IRQ
+	bicne	REG_P_REST, REG_P_REST, #FCEU_IQTEMP<<8
+	ldrne	pc, [REG_OP_TABLE, r0, lsl #2]
+	@@ I_FLAG=0 and REST is checked, we have a IRQ
+	b	do_int
+
 
 cpu_exec_end:
 	FLUSH_TIMESTAMP r0
 
 	tst	REG_P_REST, #1<<16
-	blne	do_irq_hook_noflushts
+	bne	do_irq_hook_final
 
 	ldr     r0, =nes_registers
 	stmia	r0, {r4-r12}
@@ -2920,7 +2931,6 @@ nes_internal_ram:
 	.fill	0x100, 1, 0
 nes_stack:
 	.fill	0x700, 1, 0
-@ TODO: write code which keeps it up-to-date
 pc_base:
 	.long	0
 MapIRQHook:
@@ -3048,6 +3058,7 @@ op9E:	@ SHX $nnnn, Y
 	.globl	RAM
 	.globl	timestamp
 #else
+	.globl	X_
 	.globl	nes_internal_ram
 	.globl	timestamp_a
 #endif
@@ -3152,29 +3163,60 @@ X6502_Rebase_a:
 do_irq_hook:
 	FLUSH_TIMESTAMP r0
 
-do_irq_hook_noflushts:
 	@ get irqhook cycles
 	and	r0, REG_CYCLE, #0xff00
-	bic	REG_CYCLE, REG_CYCLE, #0xff00
 	mov	r0, r0, lsr #8
 #ifndef DEBUG_ASM_6502
 	@ I have reviewed all MapIRQHook functions, they only seem to cause IRQs, not messing cycles or something
 	str     REG_P_REST, [REG_OP_TABLE, #(OTOFFS_NES_REGS + 0x10)]	@ might set irq
-	mov	REG_P_REST, lr			@ r8
+	mov	REG_P_REST, REG_OP_TABLE				@ r8
 
 	@ if somebody modifies MapIRQHook without calling reset, we are doomed
 	mov	lr, pc
 	ldr	pc, [REG_OP_TABLE, #OTOFFS_IRQ_HOOK]
 
-	ldr	REG_OP_TABLE, =cpu_exec_table	@ got trashed because was in r12
-	mov	lr, REG_P_REST
+	mov	REG_OP_TABLE, REG_P_REST				@ got trashed because was in r12
 	ldr     REG_P_REST, [REG_OP_TABLE, #(OTOFFS_NES_REGS + 0x10)]	@ might set irq
 #else
 	ldr	r1, =mapirq_cyc_a
 	str	r0, [r1]
 	mov	r1, r0
 #endif
+
+	ldrb	r0, [REG_PC], #1
+	bic	REG_CYCLE, REG_CYCLE, #0xff00
+	tst	REG_P_REST, #0xff<<8
+	ldreq	pc, [REG_OP_TABLE, r0, lsl #2]
+
+	@ do some messing to find out which IRQ is pending..
+	tst	REG_P_REST, #P_REST_I_FLAG
+	@@ if I_FLAG=1, continue execution, don't trigger IRQ
+	bicne	REG_P_REST, REG_P_REST, #FCEU_IQTEMP<<8
+	ldrne	pc, [REG_OP_TABLE, r0, lsl #2]
+	@@ I_FLAG=0 and REST is checked, we have a IRQ
+	b	do_int
+
+
+do_irq_hook_final:
+	ldr     r1, =nes_registers
+
+	@ get irqhook cycles
+	and	r0, REG_CYCLE, #0xff00
+	bic	REG_CYCLE, REG_CYCLE, #0xff00
+	mov	r0, r0, lsr #8
+
+	stmia	r1, {r4-r12}
+
+	ldmfd   r13!,{r4-r11,lr}
+
+#ifndef DEBUG_ASM_6502
+	ldr	pc, [REG_OP_TABLE, #OTOFFS_IRQ_HOOK]
+#else
+	ldr	r1, =mapirq_cyc_a
+	str	r0, [r1]
+	mov	r1, r0
 	bx	lr
+#endif
 
 
 @ vim:filetype=armasm