X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FTailCalls.h;h=a61695e7580d0d1d4fc62ec8ceb002f3de7a2faf;hb=423d477bfecd490de1449c59325c8776f91d7aac;hp=92d4f72c6b8b71263057160e2a9b677ffd982f74;hpb=4d69b633a31eb2b19141c984ffbe448b74bb5885;p=ghc-hetmet.git

diff --git a/ghc/includes/TailCalls.h b/ghc/includes/TailCalls.h
index 92d4f72..a61695e 100644
--- a/ghc/includes/TailCalls.h
+++ b/ghc/includes/TailCalls.h
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: TailCalls.h,v 1.8 2002/03/26 10:30:44 simonmar Exp $
+ * $Id: TailCalls.h,v 1.16 2004/08/13 13:09:41 simonmar Exp $
  *
  * (c) The GHC Team, 1998-1999
  *
@@ -16,7 +16,7 @@
 
 #ifdef USE_MINIINTERPRETER
 
-#define JMP_(cont) return(stgCast(StgFunPtr,cont))
+#define JMP_(cont) return((StgFunPtr)(cont))
 #define FB_
 #define FE_
 
@@ -51,15 +51,30 @@ extern void __DISCARD__(void);
 
 #define JMP_(cont)			\
     { 					\
-      void *target;			\
+      void *__target;			\
       __DISCARD__();			\
-      target = (void *)(cont);    	\
-      goto *target; 	    	    	\
+      __target = (void *)(cont);    	\
+      goto *__target; 	    	    	\
     }
 
 #endif /* i386_TARGET_ARCH */
 
 /* -----------------------------------------------------------------------------
+   Tail calling on x86_64
+   -------------------------------------------------------------------------- */
+
+#if x86_64_TARGET_ARCH
+
+#define JMP_(cont)			\
+    { 					\
+      void *__target;			\
+      __target = (void *)(cont);    	\
+      goto *__target; 	    	    	\
+    }
+
+#endif /* x86_64_TARGET_ARCH */
+
+/* -----------------------------------------------------------------------------
    Tail calling on Sparc
    -------------------------------------------------------------------------- */
 
@@ -83,11 +98,14 @@ extern void __DISCARD__(void);
 
 #ifdef alpha_TARGET_ARCH
 
+#if IN_STG_CODE
 register void *_procedure __asm__("$27");
+#endif
 
-#define JMP_(cont)	    	    	    	\
-    do { _procedure = (void *)(cont);    	\
-         goto *_procedure;    	    	    	\
+#define JMP_(cont)				\
+    do { _procedure = (void *)(cont);		\
+         __DISCARD__();				\
+         goto *_procedure;			\
        } while(0)
 
 /* Don't need these for alpha mangling */
@@ -161,19 +179,44 @@ but uses $$dyncall if necessary to cope, just in case you aren't.
     { 					\
       void *target;			\
       target = (void *)(cont);    	\
+      __DISCARD__();			\
       goto *target; 	    	    	\
     }
 
 /*
+	The __DISCARD__ is there because Apple's April 2002 Beta of GCC 3.1
+	sometimes generates incorrect code otherwise.
+	It tends to "forget" to update global register variables in the presence
+	of decrement/increment operators:
+	JMP_(*(--Sp)) is wrongly compiled as JMP_(Sp[-1]).
+	Calling __DISCARD__ in between works around this problem.
+*/
+
+/*
 	I would _love_ to use the following instead,
-	but GCC fails to generate code for it if it is called for a casted
-	data pointer - which is exactly what we are going to do...
+	but some versions of Apple's GCC fail to generate code for it
+	if it is called for a casted data pointer - which is exactly what
+	we are going to do...
 
 	#define JMP_(cont)	((F_) (cont))()
 */
 
+#endif /* powerpc_TARGET_ARCH */
 
-#endif /* sparc_TARGET_ARCH */
+/* -----------------------------------------------------------------------------
+   Tail calling on IA64
+   -------------------------------------------------------------------------- */
+
+#ifdef ia64_TARGET_ARCH
+
+/* The compiler can more intelligently decide how to do this.  We therefore
+ * implement it as a call and optimise to a jump at mangle time. */
+#define JMP_(cont)	((F_) (cont))(); __asm__ volatile ("--- TAILCALL ---");
+
+/* Don't emit calls to __DISCARD__ as this causes hassles */
+#define __DISCARD__()
+
+#endif
 
 /* -----------------------------------------------------------------------------
   FUNBEGIN and FUNEND.