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Re: Fix build with compiler defining __i686 (bug 411)


On Fri, 3 Feb 2012, Roland McGrath wrote:

> > +  ".ifndef "GET_PC_THUNK_STR(reg)";"					\
> 
> I think it's still our norm to put a space between a macro and its paren,
> even for this sort of case.  I also tend towards spaces around the "s.
> 
> It's also mostly our norm to use \n in the strings rather than ;,
> though that was not done here before.  I think that's much preferable,
> as will anyone who ever tries to read a .s file produced from this.

I think I looked at the rest of sysdeps/i386/sysdep.h to try to identify a 
norm for these macros, and found for example that ENTRY and END call a 
series of other macros without spaces.  But the file isn't consistent even 
there, and this one is of course a macro for C code rather than assembly 
source.  I'm testing this patch using newlines and spaces in the new 
macro (but still ; in the rest of the asm in check_consistency).

2012-02-04  Joseph Myers  <joseph@codesourcery.com>

	* sysdeps/i386/sysdep.h (SETUP_PIC_REG_STR, LOAD_PIC_REG_STR):
	Define.
	* sysdeps/unix/sysv/linux/i386/sysdep.h (check_consistency): Use
	LOAD_PIC_REG_STR.

diff --git a/sysdeps/i386/sysdep.h b/sysdeps/i386/sysdep.h
index a31f5e7..2c0aafa 100644
--- a/sysdeps/i386/sysdep.h
+++ b/sysdeps/i386/sysdep.h
@@ -156,4 +156,24 @@ GET_PC_THUNK(reg):							      \
 
 #define atom_text_section .section ".text.atom", "ax"
 
+#else /* __ASSEMBLER__ */
+
+# define SETUP_PIC_REG_STR(reg)						\
+  ".ifndef " GET_PC_THUNK_STR (reg) "\n"				\
+  ".section .gnu.linkonce.t." GET_PC_THUNK_STR (reg) ",\"ax\",@progbits\n" \
+  ".globl " GET_PC_THUNK_STR (reg) "\n"					\
+  ".hidden " GET_PC_THUNK_STR (reg) "\n"				\
+  ".p2align 4\n"							\
+  ".type " GET_PC_THUNK_STR (reg) ",@function\n"			\
+GET_PC_THUNK_STR (reg) ":"						\
+  "movl (%%esp), %%e" #reg "\n"						\
+  "ret\n"								\
+  ".size " GET_PC_THUNK_STR (reg) ", . - " GET_PC_THUNK_STR (reg) "\n"	\
+  ".previous\n"								\
+  ".endif\n"								\
+  "call " GET_PC_THUNK_STR (reg)
+
+# define LOAD_PIC_REG_STR(reg) \
+  SETUP_PIC_REG_STR (reg) "\naddl $_GLOBAL_OFFSET_TABLE_, %%e" #reg
+
 #endif	/* __ASSEMBLER__ */
diff --git a/sysdeps/unix/sysv/linux/i386/sysdep.h b/sysdeps/unix/sysv/linux/i386/sysdep.h
index 90660fd..efca634 100644
--- a/sysdeps/unix/sysv/linux/i386/sysdep.h
+++ b/sysdeps/unix/sysv/linux/i386/sysdep.h
@@ -514,20 +514,11 @@ asm (".L__X'%ebx = 1\n\t"
 # define check_consistency()						      \
   ({ int __res;								      \
      __asm__ __volatile__						      \
-       ("call "GET_PC_THUNK_STR(cx)";"					      \
-	"addl $_GLOBAL_OFFSET_TABLE_, %%ecx;"				      \
+       (LOAD_PIC_REG_STR(cx) ";"					      \
 	"subl %%ebx, %%ecx;"						      \
 	"je 1f;"							      \
 	"ud2;"								      \
 	"1:\n"								      \
-	".section .gnu.linkonce.t."GET_PC_THUNK_STR(cx)",\"ax\",@progbits;"   \
-	".globl "GET_PC_THUNK_STR(cx)";"				      \
-	".hidden "GET_PC_THUNK_STR(cx)";"				      \
-	".type "GET_PC_THUNK_STR(cx)",@function;"			      \
-	GET_PC_THUNK_STR(cx)":"						      \
-	"movl (%%esp), %%ecx;"						      \
-	"ret;"								      \
-	".previous"							      \
 	: "=c" (__res));						      \
      __res; })
 #endif

-- 
Joseph S. Myers
joseph@codesourcery.com


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