kernel/x86_64: rewrite cpuid.S -> cpuid.cpp

Just getting rid of some assembly, no functional change.

Signed-off-by: Paweł Dziepak <pdziepak@quarnos.org>

src/system/kernel/arch/x86/64/cpuid.S

@@ -1,47 +0,0 @@
-/*
- * Copyright 2012, Alex Smith, alex@alex-smith.me.uk.
- * Distributed under the terms of the MIT License.
- */
-
-
-#include <asm_defs.h>
-
-
-.text
-
-
-/* status_t get_current_cpuid(cpuid_info* info, uint32 eaxRegister,
-	uint32 ecxRegister) */
-FUNCTION(get_current_cpuid):
- 	push	%rbx
-	movl	%esi, %eax
-	movl	%edx, %ecx
- 	cpuid
- 	movl	%eax, 0(%rdi)
- 	movl	%ebx, 4(%rdi)
- 	movl	%edx, 8(%rdi)
- 	movl	%ecx, 12(%rdi)
- 	xorl	%eax, %eax
-		// B_OK
- 	pop		%rbx
- 	ret
-FUNCTION_END(get_current_cpuid)
-
-
-/* uint32 get_eflags(void) */
-FUNCTION(get_eflags):
-	// The top 32 bits of RFLAGS are reserved, we can ignore them.
- 	pushf
- 	pop		%rax
-	mov		%eax, %eax
- 	ret
-FUNCTION_END(get_eflags)
-
-
-/* void set_eflags(uint32 val) */
-FUNCTION(set_eflags):
-	mov		%edi, %edi
- 	push	%rdi
- 	popf
-	ret
-FUNCTION_END(set_eflags)

src/system/kernel/arch/x86/64/cpuid.cpp

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2014, Paweł Dziepak, pdziepak@quarnos.org.
+ * Copyright 2012, Alex Smith, alex@alex-smith.me.uk.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include <arch_system_info.h>
+
+
+status_t
+get_current_cpuid(cpuid_info* info, uint32 eax, uint32 ecx)
+{
+	__asm__("cpuid"
+		: "=a" (info->regs.eax), "=b" (info->regs.ebx), "=c" (info->regs.ecx),
+			"=d" (info->regs.edx)
+		: "a" (eax), "c" (ecx));
+	return B_OK;
+}
+
+
+uint32
+get_eflags()
+{
+	uint64_t flags;
+	__asm__("pushf; popq %0;" : "=r" (flags));
+	return flags;
+}
+
+
+void
+set_eflags(uint32 value)
+{
+	uint64_t flags = value;
+	__asm__("pushq %0; popf;" : : "r" (flags) : "cc");
+}
+

src/system/kernel/arch/x86/Jamfile

@@ -22,7 +22,7 @@ if $(TARGET_ARCH) = x86_64 {
 
 	archSpecificSources =
 		arch.S
-		cpuid.S
+		cpuid.cpp
 		descriptors.cpp
 		interrupts.S
 		signals.cpp