From 673d78574307b0937b71bf2821ad35b589b80221 Mon Sep 17 00:00:00 2001
From: TomW <TomW@localhost>
Date: Wed, 3 Feb 2016 21:09:05 +0000
Subject: [PATCH] Writing to a memory page with code present only causes code
 block flushes if the data changes, or if a block is currently being
 recompiled.

---
 src/386_dynarec.c |  3 +++
 src/codegen.c     |  2 ++
 src/codegen.h     |  2 ++
 src/mem.c         | 35 ++++++++++++++++++++++-------------
 4 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/src/386_dynarec.c b/src/386_dynarec.c
index c338813..8b9a999 100644
--- a/src/386_dynarec.c
+++ b/src/386_dynarec.c
@@ -1361,6 +1361,7 @@ inrecomp=0;
                         cpu_new_blocks++;
                         
                         codegen_block_init(phys_addr);
+                        codegen_in_recompile = 1;
 
 //                        if (output) pclog("Recompile block at %04x:%04x  %04x %04x %04x %04x  %04x %04x  ESP=%04x %04x  %02x%02x:%02x%02x %02x%02x:%02x%02x %02x%02x:%02x%02x\n", CS, pc, AX, BX, CX, DX, SI, DI, ESP, BP, ram[0x116330+0x6df4+0xa+3], ram[0x116330+0x6df4+0xa+2], ram[0x116330+0x6df4+0xa+1], ram[0x116330+0x6df4+0xa+0], ram[0x11d136+3],ram[0x11d136+2],ram[0x11d136+1],ram[0x11d136+0], ram[(0x119abe)+0x3],ram[(0x119abe)+0x2],ram[(0x119abe)+0x1],ram[(0x119abe)+0x0]);
                         while (!cpu_block_end)
@@ -1426,6 +1427,8 @@ inrecomp=0;
                         
                         if (x86_was_reset)
                                 codegen_reset();
+
+                        codegen_in_recompile = 0;
 //                        output &= ~2;
                 }
 //                        if (output && (SP & 1))
diff --git a/src/codegen.c b/src/codegen.c
index 8bcc6c2..8256ab2 100644
--- a/src/codegen.c
+++ b/src/codegen.c
@@ -17,3 +17,5 @@ void codegen_timing_set(codegen_timing_t *timing)
         codegen_timing_block_start = timing->block_start;
         codegen_timing_block_end = timing->block_end;
 }
+
+int codegen_in_recompile;
diff --git a/src/codegen.h b/src/codegen.h
index 23182b4..fc0132a 100644
--- a/src/codegen.h
+++ b/src/codegen.h
@@ -163,3 +163,5 @@ extern int codegen_fpu_entered;
 
 extern int codegen_fpu_loaded_iq[8];
 extern int codegen_reg_loaded[8];
+
+extern int codegen_in_recompile;
diff --git a/src/mem.c b/src/mem.c
index 2e4f33c..6a2ec9b 100644
--- a/src/mem.c
+++ b/src/mem.c
@@ -1417,28 +1417,37 @@ uint32_t mem_read_raml(uint32_t addr, void *priv)
 
 void mem_write_ramb_page(uint32_t addr, uint8_t val, page_t *p)
 {      
-        uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
+        if (val != p->mem[addr & 0xfff] || codegen_in_recompile)
+        {
+                uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
 //        pclog("mem_write_ramb_page: %08x %02x %08x %llx %llx\n", addr, val, cs+pc, p->dirty_mask, mask);
-        p->dirty_mask |= mask;
-        p->mem[addr & 0xfff] = val;
+                p->dirty_mask |= mask;
+                p->mem[addr & 0xfff] = val;
+        }
 }
 void mem_write_ramw_page(uint32_t addr, uint16_t val, page_t *p)
 {
-        uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
-        if ((addr & 0x3f) == 0x3f)
-                mask |= (mask << 1);
+        if (val != *(uint16_t *)&p->mem[addr & 0xfff] || codegen_in_recompile)
+        {
+                uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
+                if ((addr & 0x3f) == 0x3f)
+                        mask |= (mask << 1);
 //        pclog("mem_write_ramw_page: %08x %04x %08x\n", addr, val, cs+pc);
-        p->dirty_mask |= mask;
-        *(uint16_t *)&p->mem[addr & 0xfff] = val;
+                p->dirty_mask |= mask;
+                *(uint16_t *)&p->mem[addr & 0xfff] = val;
+        }
 }
 void mem_write_raml_page(uint32_t addr, uint32_t val, page_t *p)
 {       
-        uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
-        if ((addr & 0x3f) >= 0x3d)
-                mask |= (mask << 1);
+        if (val != *(uint32_t *)&p->mem[addr & 0xfff] || codegen_in_recompile)
+        {
+                uint64_t mask = (uint64_t)1 << ((addr >> PAGE_MASK_SHIFT) & PAGE_MASK_MASK);
+                if ((addr & 0x3f) >= 0x3d)
+                        mask |= (mask << 1);
 //        pclog("mem_write_raml_page: %08x %08x %08x\n", addr, val, cs+pc);
-        p->dirty_mask |= mask;
-        *(uint32_t *)&p->mem[addr & 0xfff] = val;
+                p->dirty_mask |= mask;
+                *(uint32_t *)&p->mem[addr & 0xfff] = val;
+        }
 }
 
 void mem_write_ram(uint32_t addr, uint8_t val, void *priv)