--- gforth/engine/threaded.h	2002/11/24 13:54:02	1.16
+++ gforth/engine/threaded.h	2004/06/19 14:19:44	1.26
@@ -1,6 +1,6 @@
 /* This file defines a number of threading schemes.
 
-  Copyright (C) 1995, 1996,1997,1999 Free Software Foundation, Inc.
+  Copyright (C) 1995, 1996,1997,1999,2003 Free Software Foundation, Inc.
 
   This file is part of Gforth.
 
@@ -91,144 +91,184 @@
 
 */
 
-
-
 #ifdef DOUBLY_INDIRECT
-#  define NEXT_P0	({cfa=*ip;})
+# ifndef DEBUG_DITC
+#  define DEBUG_DITC 0
+# endif
+/* define to 1 if you want to check consistency */
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	Label ca;
-#  define NEXT_P1	({\
-  if (cfa<=vm_prims+DOESJUMP || cfa>=vm_prims+npriminfos) \
+#  define NEXT_P1	do {\
+  if (DEBUG_DITC && (cfa<=vm_prims+DOESJUMP || cfa>=vm_prims+npriminfos)) \
     fprintf(stderr,"NEXT encountered prim %p at ip=%p\n", cfa, ip); \
-  ip++; ca=**cfa;})
-#  define NEXT_P2	({goto *ca;})
-#  define EXEC(XT)	({DEF_CA cfa=(XT);\
-  if (cfa>vm_prims+DOESJUMP && cfa<vm_prims+npriminfos) \
+  ip++;} while(0)
+#  define NEXT_P2	do {ca=**cfa; goto *ca;} while(0)
+#  define EXEC(XT)	do {DEF_CA cfa=(XT);\
+  if (DEBUG_DITC && (cfa>vm_prims+DOESJUMP && cfa<vm_prims+npriminfos)) \
     fprintf(stderr,"EXEC encountered xt %p at ip=%p, vm_prims=%p, xts=%p\n", cfa, ip, vm_prims, xts); \
- ca=**cfa; goto *ca;})
+ ca=**cfa; goto *ca;} while(0)
 
 #elif defined(NO_IP)
 
 #define NEXT_P0
+#  define CFA		cfa
 #define SET_IP(target)	assert(0)
 #define INC_IP(n)	((void)0)
 #define DEF_CA
 #define NEXT_P1
-#define NEXT_P2		({goto *next_code;})
+#define NEXT_P2		do {goto *next_code;} while(0)
 /* set next_code to the return address before performing EXEC */
-#define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 
 #else  /* !defined(DOUBLY_INDIRECT) && !defined(NO_IP) */
 
 #if defined(DIRECT_THREADED)
 
+/* This lets the compiler know that cfa is dead before; we place it at
+   "goto *"s that perform direct threaded dispatch (i.e., not EXECUTE
+   etc.), and thus do not reach doers, which would use cfa; the only
+   way to a doer is through EXECUTE etc., which set the cfa
+   themselves.
+
+   Some of these direct threaded schemes use "cfa" to hold the code
+   address in normal direct threaded code.  Of course we cannot use
+   KILLS there.
+
+   KILLS works by having an empty asm instruction, and claiming to the
+   compiler that it writes to cfa.
+
+   KILLS is optional.  You can write
+
+#define KILLS
+
+   and lose just a little performance.
+*/
+#define KILLS asm("":"=X"(cfa));
+
+#ifndef THREADING_SCHEME
+#define THREADING_SCHEME 7
+#endif
+
 #if THREADING_SCHEME==1
 #warning direct threading scheme 1: autoinc, long latency, cfa live
-#  define NEXT_P0	({cfa=*ip++;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip++;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip-1)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip++;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==2
 #warning direct threading scheme 2: autoinc, long latency, cfa dead
 #  define NEXT_P0	(ip++)
+#  define CFA		cfa
 #  define IP		(ip-1)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*(ip-1))
-#  define INC_IP(const_inc)	({ ip+=(const_inc);})
+#  define INC_IP(const_inc)	do { ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({goto **(ip-1);})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {KILLS goto **(ip-1);} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 
 #if THREADING_SCHEME==3
 #warning direct threading scheme 3: autoinc, low latency, cfa live
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
-#  define NEXT_P1	({cfa=*ip++;})
-#  define NEXT_P2	({goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P1	do {cfa=*ip++;} while(0)
+#  define NEXT_P2	do {goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==4
 #warning direct threading scheme 4: autoinc, low latency, cfa dead
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ ip+=(const_inc);})
+#  define INC_IP(const_inc)	do { ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({goto **(ip++);})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {KILLS goto **(ip++);} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==5
 #warning direct threading scheme 5: long latency, cfa live
-#  define NEXT_P0	({cfa=*ip;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1	(ip++)
-#  define NEXT_P2	({goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==6
 #warning direct threading scheme 6: long latency, cfa dead
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1	(ip++)
-#  define NEXT_P2	({goto **(ip-1);})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {KILLS goto **(ip-1);} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 
 #if THREADING_SCHEME==7
 #warning direct threading scheme 7: low latency, cfa live
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
-#  define NEXT_P1	({cfa=*ip++;})
-#  define NEXT_P2	({goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P1	do {cfa=*ip++;} while(0)
+#  define NEXT_P2	do {goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==8
 #warning direct threading scheme 8: cfa dead, i386 hack
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*IP)
-#  define INC_IP(const_inc)	({ ip+=(const_inc);})
+#  define INC_IP(const_inc)	do { ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1	(ip++)
-#  define NEXT_P2	({goto **(ip-1);})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {KILLS goto **(ip-1);} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==9
@@ -237,138 +277,158 @@
    this inst and the branch is 5 cycles on a PPC604; so we utilize this
    to do some prefetching in between */
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		ip
-#  define SET_IP(p)	({ip=(p); next_cfa=*ip; NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); next_cfa=*ip; NEXT_P0;} while(0)
 #  define NEXT_INST	(next_cfa)
-#  define INC_IP(const_inc)	({next_cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {next_cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	
-#  define NEXT_P1	({cfa=next_cfa; ip++; next_cfa=*ip;})
-#  define NEXT_P2	({goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P1	do {cfa=next_cfa; ip++; next_cfa=*ip;} while(0)
+#  define NEXT_P2	do {goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #  define MORE_VARS	Xt next_cfa;
 #endif
 
 #if THREADING_SCHEME==10
 #warning direct threading scheme 10: plain (no attempt at scheduling)
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({cfa=*ip++; goto *cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {cfa=*ip++; goto *cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 /* direct threaded */
 #else
 /* indirect THREADED  */
 
+#ifndef THREADING_SCHEME
+#define THREADING_SCHEME 6
+#endif
+
 #if THREADING_SCHEME==1
 #warning indirect threading scheme 1: autoinc, long latency, cisc
-#  define NEXT_P0	({cfa=*ip++;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip++;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip-1)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip++;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({goto **cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {goto **cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==2
 #warning indirect threading scheme 2: autoinc, long latency
-#  define NEXT_P0	({cfa=*ip++;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip++;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip-1)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip++;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	Label ca;
-#  define NEXT_P1	({ca=*cfa;})
-#  define NEXT_P2	({goto *ca;})
-#  define EXEC(XT)	({DEF_CA cfa=(XT); ca=*cfa; goto *ca;})
+#  define NEXT_P1	do {ca=*cfa;} while(0)
+#  define NEXT_P2	do {goto *ca;} while(0)
+#  define EXEC(XT)	do {DEF_CA cfa=(XT); ca=*cfa; goto *ca;} while(0)
 #endif
 
 
 #if THREADING_SCHEME==3
 #warning indirect threading scheme 3: autoinc, low latency, cisc
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({cfa=*ip++; goto **cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {cfa=*ip++; goto **cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==4
 #warning indirect threading scheme 4: autoinc, low latency
-#  define NEXT_P0	({cfa=*ip++;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip++;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip-1)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip++;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	Label ca;
-#  define NEXT_P1	({ca=*cfa;})
-#  define NEXT_P2	({goto *ca;})
-#  define EXEC(XT)	({DEF_CA cfa=(XT); ca=*cfa; goto *ca;})
+#  define NEXT_P1	do {ca=*cfa;} while(0)
+#  define NEXT_P2	do {goto *ca;} while(0)
+#  define EXEC(XT)	do {DEF_CA cfa=(XT); ca=*cfa; goto *ca;} while(0)
 #endif
 
 
 #if THREADING_SCHEME==5
 #warning indirect threading scheme 5: long latency, cisc
-#  define NEXT_P0	({cfa=*ip;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1	(ip++)
-#  define NEXT_P2	({goto **cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {goto **cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 #if THREADING_SCHEME==6
 #warning indirect threading scheme 6: long latency
-#  define NEXT_P0	({cfa=*ip;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	Label ca;
-#  define NEXT_P1	({ip++; ca=*cfa;})
-#  define NEXT_P2	({goto *ca;})
-#  define EXEC(XT)	({DEF_CA cfa=(XT); ca=*cfa; goto *ca;})
+#  define NEXT_P1	do {ip++; ca=*cfa;} while(0)
+#  define NEXT_P2	do {goto *ca;} while(0)
+#  define EXEC(XT)	do {DEF_CA cfa=(XT); ca=*cfa; goto *ca;} while(0)
 #endif
 
 #if THREADING_SCHEME==7
 #warning indirect threading scheme 7: low latency
-#  define NEXT_P0	({cfa=*ip;})
+#  define NEXT_P0	do {cfa1=cfa; cfa=*ip;} while(0)
+#  define CFA		cfa1
+#  define MORE_VARS     Xt cfa1;
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); cfa=*ip;} while(0)
 #  define NEXT_INST	(cfa)
-#  define INC_IP(const_inc)	({cfa=IP[const_inc]; ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {cfa=IP[const_inc]; ip+=(const_inc);} while(0)
 #  define DEF_CA	Label ca;
-#  define NEXT_P1	({ip++; ca=*cfa;})
-#  define NEXT_P2	({goto *ca;})
-#  define EXEC(XT)	({DEF_CA cfa=(XT); ca=*cfa; goto *ca;})
+#  define NEXT_P1	do {ip++; ca=*cfa;} while(0)
+#  define NEXT_P2	do {goto *ca;} while(0)
+#  define EXEC(XT)	do {DEF_CA cfa=(XT); ca=*cfa; goto *ca;} while(0)
 #endif
 
 #if THREADING_SCHEME==8
 #warning indirect threading scheme 8: low latency,cisc
 #  define NEXT_P0
+#  define CFA		cfa
 #  define IP		(ip)
-#  define SET_IP(p)	({ip=(p); NEXT_P0;})
+#  define SET_IP(p)	do {ip=(p); NEXT_P0;} while(0)
 #  define NEXT_INST	(*ip)
-#  define INC_IP(const_inc)	({ip+=(const_inc);})
+#  define INC_IP(const_inc)	do {ip+=(const_inc);} while(0)
 #  define DEF_CA
 #  define NEXT_P1
-#  define NEXT_P2	({cfa=*ip++; goto **cfa;})
-#  define EXEC(XT)	({cfa=(XT); goto **cfa;})
+#  define NEXT_P2	do {cfa=*ip++; goto **cfa;} while(0)
+#  define EXEC(XT)	do {cfa=(XT); goto **cfa;} while(0)
 #endif
 
 /* indirect threaded */
@@ -376,5 +436,5 @@
 
 #endif /* !defined(DOUBLY_INDIRECT) && !defined(NO_IP) */
 
-#define NEXT ({DEF_CA NEXT_P1; NEXT_P2;})
+#define NEXT do {DEF_CA NEXT_P1; NEXT_P2;} while(0)
 #define IPTOS NEXT_INST