Mon Jun 10 17:50:31 1996 David Mosberger-Tang <davidm@azstarnet.com>

	* sysdeps/unix/alpha/sysdep.h: Move error-handling code in PSEUDO
 	to PSEUDO_END to improve branch-prediction.  Include .frame
 	directive to make syscalls debugabble.
	(PSEUDO_END): New macro.
	* sysdeps/unix/alpha/sysdep.h, sysdeps/alpha/bb_init_func.S,
 	sysdeps/unix/sysv/linux/alpha/brk.S: Use ldiq instead of ldi since
 	latter is illegal under DEC Unix.

diff --git a/sysdeps/unix/alpha/sysdep.h b/sysdeps/unix/alpha/sysdep.h
index 6fed4a6..4b3f9aa 100644 (file)
--- a/sysdeps/unix/alpha/sysdep.h
+++ b/sysdeps/unix/alpha/sysdep.h
@@ -58,25 +58,27 @@ Cambridge, MA 02139, USA.  */
   .frame sp, 0, ra
 #endif
 
-/* Note that while it's better structurally, going back to set errno
-   can make things confusing if you're debugging---it looks like it's jumping
-   backwards into the previous fn.  */
+/* Mark the end of function SYM.  */
+#undef END
+#define END(sym)       .end sym
+
+/* Note that PSEUDO/PSEUDO_END use label number 1996---do not use a
+   label of that number between those two macros!  */
+ 
 #ifdef __STDC__
 #define PSEUDO(name, syscall_name, args)       \
     .globl name;                               \
     .align 3;                                  \
     .ent name,0;                               \
                                                \
-1:  br         gp, 2f;                         \
-2:  ldgp       gp, 0(gp);                      \
-    jmp                zero, syscall_error;            \
-                                               \
 name##:                                                \
-    ldi                v0, SYS_ify(syscall_name);      \
+    .frame sp, 0, ra                           \
+    .prologue 1; /* yes, we do use gp */       \
+    ldiq       v0, SYS_ify(syscall_name);      \
     .set noat;                                 \
     call_pal   PAL_callsys;                    \
     .set at;                                   \
-    bne                a3, 1b;                         \
+    bne                a3, 1996f;                      \
 3:
 #else
 #define PSEUDO(name, syscall_name, args)       \
@@ -84,21 +86,35 @@ name##:                                             \
     .align 3;                                  \
     .ent name,0;                               \
                                                \
-1:  br         gp, 2f;                         \
-2:  ldgp       gp, 0(gp);                      \
-    jmp                zero, syscall_error;            \
-                                               \
 name/**/:                                      \
-    ldi                v0, SYS_ify(syscall_name);      \
+    .frame sp, 0, ra                           \
+    .prologue 1; /* yes, we do use gp */       \
+    ldiq       v0, SYS_ify(syscall_name);      \
     .set noat;                                 \
     call_pal   PAL_callsys;                    \
     .set at;                                   \
-    bne                a3, 1b;                         \
+    bne                a3, 1996f;                      \
 3:
 #endif
 
-#undef END
-#define END(sym)       .end sym
+#undef PSEUDO_END
+
+#ifdef PIC
+/* When building a shared library, we can use a branch since the text
+   section of the library is much smaller than 4MB.  If we ever break
+   this assumption, the linker will tell us.  */
+# define PSEUDO_END(sym)                       \
+1996:                                          \
+    br         zero, __syscall_error;          \
+    END(sym)
+#else
+# define PSEUDO_END(sym)                       \
+1996:                                          \
+    br         gp, 2f;                         \
+2:  ldgp       gp, 0(gp);                      \
+    jmp                zero, __syscall_error;          \
+    END(sym)
+#endif
 
 #define r0     v0
 #define r1     a4