2009-06-04 Vladimir Serbinenko <phcoder@gmail.com>

	Avoid clobbering %ebx/%rbx in inline assembly with Apple's CC

	* efiemu/runtime/efiemu.c (write_cmos): use %cl instead of %bl as
	temporary storage
	* include/grub/i386/tsc.h (grub_get_tsc): restore %rbx/%ebx when
	using Apple's CC
	(grub_cpu_is_tsc_supported): likewise
	* loader/i386/xnu.c (guessfsb): restore %rbx/%ebx in inline assembly

diff --git a/ChangeLog b/ChangeLog
index 4c63b31071163ce695fbb0ec517a7c64be086f62..01fc3a232c8a9b82d32bfe90c147f150b0453615 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2009-06-04  Vladimir Serbinenko  <phcoder@gmail.com>
+
+       Avoid clobbering %ebx/%rbx in inline assembly with Apple's CC
+
+       * efiemu/runtime/efiemu.c (write_cmos): use %cl instead of %bl as
+       temporary storage
+       * include/grub/i386/tsc.h (grub_get_tsc): restore %rbx/%ebx when 
+       using Apple's CC 
+       (grub_cpu_is_tsc_supported): likewise
+       * loader/i386/xnu.c (guessfsb): restore %rbx/%ebx in inline assembly
+       
 2009-06-04  Vladimir Serbinenko  <phcoder@gmail.com>
 
        Absolute addressing through constant with Apple's cc

diff --git a/efiemu/runtime/efiemu.c b/efiemu/runtime/efiemu.c
index 5887c48ab7392c14d3f3b00de659170ed950ed45..f73f843eaf07f14258e2add0efc7671c83e5bb65 100644 (file)
--- a/efiemu/runtime/efiemu.c
+++ b/efiemu/runtime/efiemu.c
@@ -162,8 +162,8 @@ static inline void
 write_cmos (grub_uint8_t addr, grub_uint8_t val)
 {
   __asm__ __volatile__ ("outb %%al,$0x70\n"
-                       "mov %%bl, %%al\n"
-                       "outb %%al,$0x71": :"a" (addr), "b" (val));
+                       "mov %%cl, %%al\n"
+                       "outb %%al,$0x71": :"a" (addr), "c" (val));
 }
 
 static inline grub_uint8_t

diff --git a/include/grub/i386/tsc.h b/include/grub/i386/tsc.h
index 963370113a2e280f7951761f3589938fbff48a8f..aa4014575acedde4cfaec2d483cb5f152e2ac961 100644 (file)
--- a/include/grub/i386/tsc.h
+++ b/include/grub/i386/tsc.h
@@ -29,8 +29,24 @@ grub_get_tsc (void)
 
   /* The CPUID instruction is a 'serializing' instruction, and
      avoids out-of-order execution of the RDTSC instruction. */
+#ifdef APPLE_CC
   __asm__ __volatile__ ("xorl %%eax, %%eax\n\t"
-                        "cpuid":::"%rax", "%rbx", "%rcx", "%rdx");
+#ifdef __x86_64__
+                       "push %%rbx\n"
+#else
+                       "push %%ebx\n"
+#endif
+                       "cpuid\n"
+#ifdef __x86_64__
+                       "pop %%rbx\n"
+#else
+                       "pop %%ebx\n"
+#endif 
+                       :::"%rax", "%rcx", "%rdx");
+#else
+  __asm__ __volatile__ ("xorl %%eax, %%eax\n\t"
+                       "cpuid":::"%rax", "%rbx", "%rcx", "%rdx");
+#endif
   /* Read TSC value.  We cannot use "=A", since this would use
      %rax on x86_64. */
   __asm__ __volatile__ ("rdtsc":"=a" (lo), "=d" (hi));
@@ -93,11 +109,29 @@ grub_cpu_is_tsc_supported (void)
     return 0;
 
   grub_uint32_t features;
+#ifdef APPLE_CC
   __asm__ ("movl $1, %%eax\n\t"
-           "cpuid"
+#ifdef __x86_64__
+          "push %%rbx\n"
+#else
+          "push %%ebx\n"
+#endif
+          "cpuid\n"
+#ifdef __x86_64__
+          "pop %%rbx\n"
+#else
+          "pop %%ebx\n"
+#endif
+           : "=d" (features)
+           : /* No inputs.  */
+          : /* Clobbered:  */ "%rax", "%rcx");
+#else
+  __asm__ ("movl $1, %%eax\n\t"
+           "cpuid\n"
            : "=d" (features)
            : /* No inputs.  */
            : /* Clobbered:  */ "%rax", "%rbx", "%rcx");
+#endif
   return (features & (1 << 4)) != 0;
 }
 

diff --git a/loader/i386/xnu.c b/loader/i386/xnu.c
index 0860160249496b5d0397f1825e37517631e50d8d..c0e731c090069a79b7540ebccee8d3400e0c44f9 100644 (file)
--- a/loader/i386/xnu.c
+++ b/loader/i386/xnu.c
@@ -125,6 +125,28 @@ guessfsb (void)
 
   if (! grub_cpu_is_cpuid_supported ())
     return sane_value;
+       
+#ifdef APPLE_CC
+  asm volatile ("movl $0, %%eax\n"
+#ifdef __x86_64__
+               "push %%rbx\n"
+#else
+               "push %%ebx\n"
+#endif
+               "cpuid\n"
+#ifdef __x86_64__
+               "pop %%rbx\n"
+#else
+               "pop %%ebx\n"
+#endif                           
+               : "=a" (max_cpuid), 
+                 "=d" (manufacturer[1]), "=c" (manufacturer[2]));
+  
+  /* Only Intel for now is done. */
+  if (grub_memcmp (manufacturer + 1, "ineIntel", 12) != 0)
+    return sane_value;
+  
+#else
   asm volatile ("movl $0, %%eax\n"
                "cpuid"
                : "=a" (max_cpuid), "=b" (manufacturer[0]), 
@@ -133,15 +155,33 @@ guessfsb (void)
   /* Only Intel for now is done. */
   if (grub_memcmp (manufacturer, "GenuineIntel", 12) != 0)
     return sane_value;
+#endif
 
   /* Check Speedstep. */
   if (max_cpuid < 1)
     return sane_value;
 
+#ifdef APPLE_CC
+  asm volatile ("movl $1, %%eax\n"
+#ifdef __x86_64__
+               "push %%rbx\n"
+#else
+               "push %%ebx\n"
+#endif                           
+               "cpuid\n"
+#ifdef __x86_64__
+               "pop %%rbx\n"
+#else
+               "pop %%ebx\n"
+#endif
+               : "=c" (capabilities):
+               : "%rax", "%rdx");      
+#else
   asm volatile ("movl $1, %%eax\n"
                "cpuid"
                : "=c" (capabilities):
-               : "%eax", "%ebx", "%edx");
+               : "%rax", "%rbx", "%rdx");
+#endif
 
   if (! (capabilities & (1 << 7)))
     return sane_value;