From e95f5491bc4172f76d98f79de40a36098152937c Mon Sep 17 00:00:00 2001
From: aurel32 <aurel32@c046a42c-6fe2-441c-8c8c-71466251a162>
Date: Sun, 12 Oct 2008 00:53:17 +0000
Subject: [PATCH] hw/apic.c: use __builtin funtions instead of assembly code

Suggested by malc.

Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5465 c046a42c-6fe2-441c-8c8c-71466251a162
---
 hw/apic.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/hw/apic.c b/hw/apic.c
index 0f661b61fe..46daf8a33a 100644
--- a/hw/apic.c
+++ b/hw/apic.c
@@ -104,15 +104,14 @@ static void apic_init_ipi(APICState *s);
 static void apic_set_irq(APICState *s, int vector_num, int trigger_mode);
 static void apic_update_irq(APICState *s);
 
-/* Find first bit starting from msb. Return 0 if value = 0 */
+/* Find first bit starting from msb */
 static int fls_bit(uint32_t value)
 {
+#if defined(__GNUC__)
+    return 31 - __builtin_clz(value);
+#else
     unsigned int ret = 0;
 
-#if defined(HOST_I386) || defined(HOST_X86_64)
-    __asm__ __volatile__ ("bsr %1, %0\n" : "+r" (ret) : "rm" (value));
-    return ret;
-#else
     if (value > 0xffff)
         value >>= 16, ret = 16;
     if (value > 0xff)
@@ -125,15 +124,14 @@ static int fls_bit(uint32_t value)
 #endif
 }
 
-/* Find first bit starting from lsb. Return 0 if value = 0 */
+/* Find first bit starting from lsb */
 static int ffs_bit(uint32_t value)
 {
+#if defined(__GNUC__)
+    return __builtin_ffs(value) - 1;
+#else
     unsigned int ret = 0;
 
-#if defined(HOST_I386) || defined(HOST_X86_64)
-    __asm__ __volatile__ ("bsf %1, %0\n" : "+r" (ret) : "rm" (value));
-    return ret;
-#else
     if (!value)
         return 0;
     if (!(value & 0xffff))
-- 
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