[kvm-unit-tests PATCH v2 4/5] x86: Dedup 32-bit vs. 64-bit ASM_TRY() by stealing kernel's __ASM_SEL()

[Michal Luczaj <mhal@rbox.co>]

From: Sean Christopherson <seanjc@google.com>

Steal the kernel's __ASM_SEL() implementation and use it to consolidate
ASM_TRY().  The only difference between the 32-bit and 64-bit versions is
the size of the address stored in the table.

No functional change intended.

Signed-off-by: Michal Luczaj <mhal@rbox.co>
---
 lib/x86/desc.h      | 22 ++++++----------------
 lib/x86/processor.h | 12 ++++++++++++
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/lib/x86/desc.h b/lib/x86/desc.h
index 8854fcc..5bb6fcb 100644
--- a/lib/x86/desc.h
+++ b/lib/x86/desc.h
@@ -80,23 +80,13 @@ typedef struct  __attribute__((packed)) {
 	u16 iomap_base;
 } tss64_t;
 
-#ifdef __x86_64
-#define __ASM_TRY(prefix, catch)	\
-	"movl $0, %%gs:4 \n\t"		\
-	".pushsection .data.ex \n\t"	\
-	".quad 1111f, " catch "\n\t"	\
-	".popsection \n\t"		\
-	prefix				\
+#define __ASM_TRY(prefix, catch)				\
+	"movl $0, %%gs:4 \n\t"					\
+	".pushsection .data.ex \n\t"				\
+	__ASM_SEL(.long, .quad) " 1111f,  " catch "\n\t"	\
+	".popsection \n\t"					\
+	prefix							\
 	"1111:"
-#else
-#define __ASM_TRY(prefix, catch)	\
-	"movl $0, %%gs:4 \n\t"		\
-	".pushsection .data.ex \n\t"	\
-	".long 1111f, " catch "\n\t"	\
-	".popsection \n\t"		\
-	prefix				\
-	"1111:"
-#endif
 
 #define ASM_TRY(catch) __ASM_TRY("", catch)
 
diff --git a/lib/x86/processor.h b/lib/x86/processor.h
index 0324220..30e2de8 100644
--- a/lib/x86/processor.h
+++ b/lib/x86/processor.h
@@ -19,6 +19,18 @@
 #  define S "4"
 #endif
 
+#ifdef __ASSEMBLY__
+#define __ASM_FORM(x, ...)	x,## __VA_ARGS__
+#else
+#define __ASM_FORM(x, ...)	" " xstr(x,##__VA_ARGS__) " "
+#endif
+
+#ifndef __x86_64__
+#define __ASM_SEL(a,b)		__ASM_FORM(a)
+#else
+#define __ASM_SEL(a,b)		__ASM_FORM(b)
+#endif
+
 #define DB_VECTOR 1
 #define BP_VECTOR 3
 #define UD_VECTOR 6
-- 
2.37.1