diff: runtime/calls.h fixes

[Fergus Henderson]

runtime/goto.h:
	Define NEEDS_ASM_FIXUP_REGS iff ASM_FIXUP_REGS is non-empty
	(for use by calls.h).

runtime/calls.h:
	Use NEEDS_ASM_FIXUP_REGS and ASM_FIXUP_REGS (defined in goto.h)
	to handle register restores on return from procedure calls,
	rather than hard-coding it specifically for __alpha__.
	This ensures that all the architecture-specific code for
	handling non-local gotos is localized in the start of goto.h.

cvs diff: Diffing .
Index: calls.h
===================================================================
RCS file: /home/staff/zs/imp/mercury/runtime/calls.h,v
retrieving revision 1.2
diff -u -r1.2 calls.h
--- calls.h	1997/02/12 02:15:07	1.2
+++ calls.h	1997/05/26 16:34:59
@@ -22,8 +22,13 @@
 			GOTO_LABEL(label);			\
 		} while (0)
 
-#if defined(__alpha__) && defined(USE_ASM_LABELS)
-#define	noprof_call(proc, succ_cont)				\
+/*
+** On some systems [basically those using PIC (Position Independent Code)],
+** if we're using gcc non-local gotos to jump between functions then
+** we need to do ASM_FIXUP_REGS after each return from a procedure call.
+*/
+#if defined(USE_GCC_NONLOCAL_GOTOS) && defined(NEED_ASM_FIXUP_REGS)
+  #define	noprof_call(proc, succ_cont)			\
 		({						\
 			__label__ fixup_gp;			\
 			debugcall((proc), (succ_cont));		\
@@ -31,14 +36,11 @@
 			set_prof_current_proc(proc);		\
 			GOTO(proc);				\
 		fixup_gp:					\
-			__asm__ __volatile__ (			\
-				"ldgp $gp, 0($27)"		\
-				: : : "memory"			\
-			);					\
+			ASM_FIXUP_REGS				\
 			GOTO(succ_cont); 			\
 		})
 	/* same as above, but with GOTO_LABEL rather than GOTO */
-#define	noprof_call_localret(proc, succ_cont)			\
+  #define	noprof_call_localret(proc, succ_cont)		\
 		({						\
 			__label__ fixup_gp;			\
 			debugcall((proc), (succ_cont));		\
@@ -46,21 +48,18 @@
 			set_prof_current_proc(proc);		\
 			GOTO(proc);				\
 		fixup_gp:					\
-			__asm__ __volatile__ (			\
-				"ldgp $gp, 0($27)"		\
-				: : : "memory"			\
-			);					\
+			ASM_FIXUP_REGS				\
 			GOTO_LABEL(succ_cont); 			\
 		})
 #else
-#define	noprof_call(proc, succ_cont)				\
+  #define	noprof_call(proc, succ_cont)			\
 		do {						\
 			debugcall((proc), (succ_cont));		\
 			succip = (succ_cont);			\
 			set_prof_current_proc(proc);		\
 			GOTO(proc);				\
 		} while (0)
-#define noprof_call_localret(proc, succ_cont) 			\
+  #define noprof_call_localret(proc, succ_cont) 		\
 		noprof_call((proc), LABEL(succ_cont))
 #endif
 
Index: goto.h
===================================================================
RCS file: /home/staff/zs/imp/mercury/runtime/goto.h,v
retrieving revision 1.28
diff -u -r1.28 goto.h
--- goto.h	1997/02/16 12:08:05	1.28
+++ goto.h	1997/05/26 16:31:28
@@ -266,9 +266,11 @@
 	__asm__ __volatile__(				\
 		INLINE_ASM_FIXUP_REGS			\
 	);
+#define NEED_ASM_FIXUP_REGS
 #else
 #define ASM_FIXUP_REGS
 #define INLINE_ASM_FIXUP_REGS
+#undef  NEED_ASM_FIXUP_REGS
 #endif
 
 /*
cvs diff: Diffing machdeps

-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.