From 141ac468abbd1f1d17d8969e8ee1b62cce65091e Mon Sep 17 00:00:00 2001
From: blueswir1 <blueswir1@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Sat, 26 Jul 2008 15:05:57 +0000
Subject: [PATCH] Map code buffers below 2G on Sparc64

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4951 c046a42c-6fe2-441c-8c8c-71466251a162
---
 exec.c     | 18 +++++++++++++-----
 sparc64.ld |  1 +
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/exec.c b/exec.c
index 47f35e5b2e..3ab4ad059e 100644
--- a/exec.c
+++ b/exec.c
@@ -89,9 +89,9 @@ int nb_tbs;
 /* any access to the tbs or the page table must use this lock */
 spinlock_t tb_lock = SPIN_LOCK_UNLOCKED;
 
-#if defined(__arm__)
-/* The prologue must be reachable with a direct jump. ARM has a
- limited branch range (possibly also PPC and SPARC?) so place it in a
+#if defined(__arm__) || defined(__sparc_v9__)
+/* The prologue must be reachable with a direct jump. ARM and Sparc64
+ have limited branch ranges (possibly also PPC) so place it in a
  section close to code segment. */
 #define code_gen_section                                \
     __attribute__((__section__(".gen_code")))           \
@@ -410,15 +410,23 @@ void code_gen_alloc(unsigned long tb_size)
 #if defined(__linux__) 
     {
         int flags;
+        void *start = NULL;
+
         flags = MAP_PRIVATE | MAP_ANONYMOUS;
 #if defined(__x86_64__)
         flags |= MAP_32BIT;
         /* Cannot map more than that */
         if (code_gen_buffer_size > (800 * 1024 * 1024))
             code_gen_buffer_size = (800 * 1024 * 1024);
+#elif defined(__sparc_v9__)
+        // Map the buffer below 2G, so we can use direct calls and branches
+        flags |= MAP_FIXED;
+        start = (void *) 0x60000000UL;
+        if (code_gen_buffer_size > (512 * 1024 * 1024))
+            code_gen_buffer_size = (512 * 1024 * 1024);
 #endif
-        code_gen_buffer = mmap(NULL, code_gen_buffer_size,
-                               PROT_WRITE | PROT_READ | PROT_EXEC, 
+        code_gen_buffer = mmap(start, code_gen_buffer_size,
+                               PROT_WRITE | PROT_READ | PROT_EXEC,
                                flags, -1, 0);
         if (code_gen_buffer == MAP_FAILED) {
             fprintf(stderr, "Could not allocate dynamic translator buffer\n");
diff --git a/sparc64.ld b/sparc64.ld
index 54d2f7dd85..f7286346c3 100644
--- a/sparc64.ld
+++ b/sparc64.ld
@@ -69,6 +69,7 @@ SECTIONS
   . = ALIGN(0x100000) + (. & (0x100000 - 1));
   .data    :
   {
+    *(.gen_code)
     *(.data)
     *(.gnu.linkonce.d*)
     CONSTRUCTORS