From: notaz <notasas@gmail.com>
Date: Sun, 31 Jul 2011 20:50:19 +0000 (+0300)
Subject: drc: fix page get code in linkage_arm.s
X-Git-Tag: r9~21
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?p=pcsx_rearmed.git;a=commitdiff_plain;h=f968d35dc0302f3fb7fba5a1bafb5feed1f758f6;hp=b17618c006c1a79ea0aa38c5e452a384f7f2bc95

drc: fix page get code in linkage_arm.s

it did not match what was used elsewhere for PCSX,
causing rare crashes due to making bad links..

Also comment get_pointer, it's not obvious what it does.
---

diff --git a/libpcsxcore/new_dynarec/assem_arm.c b/libpcsxcore/new_dynarec/assem_arm.c
index 0c668d36..33ecf8e1 100644
--- a/libpcsxcore/new_dynarec/assem_arm.c
+++ b/libpcsxcore/new_dynarec/assem_arm.c
@@ -186,11 +186,15 @@ void *kill_pointer(void *stub)
   return i_ptr;
 }
 
+// find where external branch is liked to using addr of it's stub:
+// get address that insn one after stub loads (dyna_linker arg1),
+// treat it as a pointer to branch insn,
+// return addr where that branch jumps to
 int get_pointer(void *stub)
 {
   //printf("get_pointer(%x)\n",(int)stub);
   int *ptr=(int *)(stub+4);
-  assert((*ptr&0x0ff00000)==0x05900000);
+  assert((*ptr&0x0fff0000)==0x059f0000);
   u_int offset=*ptr&0xfff;
   int **l_ptr=(void *)ptr+offset+8;
   int *i_ptr=*l_ptr;
diff --git a/libpcsxcore/new_dynarec/linkage_arm.s b/libpcsxcore/new_dynarec/linkage_arm.s
index 6107e270..b22d491f 100644
--- a/libpcsxcore/new_dynarec/linkage_arm.s
+++ b/libpcsxcore/new_dynarec/linkage_arm.s
@@ -219,14 +219,16 @@ dynarec_local_end = memory_map + 4194304
 dyna_linker:
 	/* r0 = virtual target address */
 	/* r1 = instruction to patch */
-	mov	r12, r0
-	mov	r6, #4096
-	mov	r2, #0x80000
 	ldr	r3, .jiptr
+	/* get_page */
+	lsr     r2, r0, #12
+	mov	r6, #4096
+	bic	r2, r2, #0xe0000
 	sub	r6, r6, #1
+	cmp     r2, #0x1000
 	ldr	r7, [r1]
-	eor	r2, r2, r12, lsr #12
-	and	r6, r6, r12, lsr #12
+	biclt   r2, #0x0e00
+	and	r6, r6, r2
 	cmp	r2, #2048
 	add	r12, r7, #2
 	orrcs	r2, r6, #2048
@@ -337,14 +339,16 @@ exec_pagefault:
 dyna_linker_ds:
 	/* r0 = virtual target address */
 	/* r1 = instruction to patch */
-	mov	r12, r0
-	mov	r6, #4096
-	mov	r2, #0x80000
 	ldr	r3, .jiptr
+	/* get_page */
+	lsr     r2, r0, #12
+	mov	r6, #4096
+	bic	r2, r2, #0xe0000
 	sub	r6, r6, #1
+	cmp     r2, #0x1000
 	ldr	r7, [r1]
-	eor	r2, r2, r12, lsr #12
-	and	r6, r6, r12, lsr #12
+	biclt   r2, #0x0e00
+	and	r6, r6, r2
 	cmp	r2, #2048
 	add	r12, r7, #2
 	orrcs	r2, r6, #2048