IGEN - Replace IMEM (IMEM_IMMED) macro with IMEM<insn-size> macro,

update v850, tic80 and mips simulators.
IGEN - Prepend prefix to more generated symbols and macros
(idecode_issue, instruction_word).
IGEN - Add -Wnowith option to supress warnings about word size
inflicts in input files.
MIPS - Clean up Makefile.in, m16.igen, m16.dc (new), m16run.c (new) so
that a mips16 simulator built using IGEN can be compiled.

5 files changed, 216 insertions, 73 deletions

diff --git a/sim/mips/ChangeLog b/sim/mips/ChangeLog
index ba1ba1a..a823f12 100644
--- a/sim/mips/ChangeLog
+++ b/sim/mips/ChangeLog
@@ -1,3 +1,44 @@
+Tue Feb  3 11:36:02 1998  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* interp.c (ifetch16): New function.
+
+	* sim-main.h (IMEM32): Rename IMEM.
+	(IMEM16_IMMED): Define.
+	(IMEM16): Define.
+	(DELAY_SLOT): Update.
+	
+	* m16run.c (sim_engine_run): New file.
+	
+	* m16.igen: All instructions except LB.
+	(LB): Call do_load_byte.
+	* mips.igen (do_load_byte): New function.
+	(LB): Call do_load_byte.
+
+	* mips.igen: Move spec for insn bit size and high bit from here.
+	* Makefile.in (tmp-igen, tmp-m16): To here.
+
+	* m16.dc: New file, decode mips16 instructions.
+
+	* Makefile.in (SIM_NO_ALL): Define.
+	(tmp-m16): Generate both 16 bit and 32 bit simulator engines.
+
+start-sanitize-tx19
+	* m16.igen: Mark all mips16 insns as being part of the tx19 insn
+ 	set.
+
+end-sanitize-tx19
+Tue Feb  3 11:28:00 1998  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* configure.in (mips_fpu_bitsize): For tx39, restrict floating
+ 	point unit to 32 bit registers.
+	* configure: Re-generate.
+
+Sun Feb  1 15:47:14 1998  Andrew Cagney  <cagney@b1.cygnus.com>
+
+	* configure.in (sim_use_gen): Make IGEN the default simulator
+ 	generator for generic 32 and 64 bit mips targets.
+	* configure: Re-generate.
+
 Sun Feb  1 16:52:37 1998  Andrew Cagney  <cagney@b1.cygnus.com>
 
 	* sim-main.h (SizeFGR): Determine from floating-point and not gpr
diff --git a/sim/mips/Makefile.in b/sim/mips/Makefile.in
index 608486a..83b89c4 100644
--- a/sim/mips/Makefile.in
+++ b/sim/mips/Makefile.in
@@ -15,41 +15,31 @@ SIM_IGEN_OBJ = \
 	idecode.o \
 	icache.o \
 	engine.o \
-	irun.o
+	irun.o \
 
 SIM_M16_OBJ = \
-	$(SIM_IGEN_OBJ) = \
 	m16_support.o \
-	m16_itable.o \
 	m16_semantics.o \
 	m16_idecode.o \
 	m16_icache.o \
-	m16_engine.o \
-	m16_irun.o
+	\
+	m32_support.o \
+	m32_semantics.o \
+	m32_idecode.o \
+	m32_icache.o \
+	\
+	itable.o \
+	m16run.o \
 
 SIM_OBJS = \
 	$(SIM_@sim_gen@_OBJ) \
+	$(SIM_NEW_COMMON_OBJS) \
 	interp.o \
-	sim-bits.o \
-	sim-load.o \
-	sim-utils.o \
 	sim-hload.o \
-	sim-io.o \
-	sim-config.o \
-	sim-endian.o \
 	sim-engine.o \
-	sim-memopt.o \
 	sim-stop.o \
 	sim-resume.o \
 	sim-reason.o \
-	sim-events.o \
-	sim-module.o \
-	sim-trace.o \
-	sim-options.o \
-	sim-profile.o \
-	sim-core.o \
-	sim-watch.o
-
 
 
 # List of flags to always pass to $(CC).
@@ -77,7 +67,16 @@ SIM_RUN_OBJS = nrun.o
 
 ## COMMON_POST_CONFIG_FRAG
 
-interp.o: $(srcdir)/interp.c config.h sim-main.h oengine.c
+SIM_NO_INTERP = oengine.c
+interp.o: $(srcdir)/interp.c config.h sim-main.h $(SIM_@sim_gen@_INTERP)
+
+
+
+#
+# Old deprecated generator
+#
+
+SIM_NO_ALL = oengine.c
 
 oengine.c: gencode
 	./gencode @SIMCONF@ > tmp-oengine
@@ -95,18 +94,21 @@ getopt1.o: $(srcdir)/../../libiberty/getopt1.c
 	$(CC_FOR_BUILD) -c -g -I${srcroot}/include $(srcdir)/../../libiberty/getopt1.c
 
 
+
 ../igen/igen:
 	cd ../igen && $(MAKE)
 
 IGEN_TRACE= # -G omit-line-numbers # -G trace-rule-selection -G trace-rule-rejection -G trace-entries
 IGEN_INSN=$(srcdir)/mips.igen
 IGEN_DC=$(srcdir)/mips.dc
+M16_DC=$(srcdir)/m16.dc
 IGEN_INCLUDE=\
 	$(start-sanitize-r5900) \
 	$(srcdir)/r5900.igen \
 	$(end-sanitize-r5900) \
 	$(start-sanitize-vr5400) \
 	$(srcdir)/vr5400.igen \
+	$(srcdir)/mdmx.igen \
 	$(end-sanitize-vr5400) \
 	$(srcdir)/m16.igen
 
@@ -145,6 +147,9 @@ tmp-igen: $(IGEN_INSN) $(IGEN_DC) ../igen/igen $(IGEN_INCLUDE)
 		-Wnodiscard \
 		@sim_igen_flags@ \
 		-G gen-direct-access \
+		-G gen-zero-r0 \
+		-B 32 \
+		-H 31 \
 		-i $(IGEN_INSN) \
 		-o $(IGEN_DC) \
 		-x \
@@ -188,7 +193,7 @@ itable.o: sim-main.h $(SIM_EXTRA_DEPS)
 
 
 
-SIM_M16_ALL = tmp-igen $(SIM_M16_ALL) 
+SIM_M16_ALL = tmp-m16
 
 BUILT_SRC_FROM_M16 = \
 	m16_icache.h \
@@ -201,11 +206,20 @@ BUILT_SRC_FROM_M16 = \
 	m16_model.c \
 	m16_support.h \
 	m16_support.c \
-	m16_itable.h \
-	m16_itable.c \
-	m16_engine.h \
-	m16_engine.c \
-	m16_irun.c
+	\
+	m32_icache.h \
+	m32_icache.c \
+	m32_idecode.h \
+	m32_idecode.c \
+	m32_semantics.h \
+	m32_semantics.c \
+	m32_model.h \
+	m32_model.c \
+	m32_support.h \
+	m32_support.c \
+	\
+	itable.h \
+	itable.c \
 
 $(BUILT_SRC_FROM_M16): tmp-m16
 
@@ -221,11 +235,14 @@ tmp-m16: $(IGEN_INSN) $(IGEN_DC) ../igen/igen $(IGEN_INCLUDE)
 		-I $(srcdir) \
 		-Werror \
 		-Wnodiscard \
-		-F 16 \
-		-M mips16 \
+		@sim_m16_flags@ \
 		-G gen-direct-access \
+		-G gen-zero-r0 \
+		-B 16 \
+		-H 15 \
 		-i $(IGEN_INSN) \
-		-o $(IGEN_DC) \
+		-o $(M16_DC) \
+		-P m16_ \
 		-x \
 		-n m16_icache.h    -hc tmp-icache.h \
 		-n m16_icache.c    -c  tmp-icache.c \
@@ -237,11 +254,7 @@ tmp-m16: $(IGEN_INSN) $(IGEN_DC) ../igen/igen $(IGEN_INCLUDE)
 		-n m16_model.c     -m  tmp-model.c \
 		-n m16_support.h   -hf tmp-support.h \
 		-n m16_support.c   -f  tmp-support.c \
-		-n m16_itable.h    -ht tmp-itable.h \
-		-n m16_itable.c    -t  tmp-itable.c \
-		-n m16_engine.h    -he tmp-engine.h \
-		-n m16_engine.c    -e  tmp-engine.c \
-		-n m16_irun.c      -r  tmp-irun.c
+		#
 	$(srcdir)/../../move-if-change tmp-icache.h m16_icache.h
 	$(srcdir)/../../move-if-change tmp-icache.c m16_icache.c
 	$(srcdir)/../../move-if-change tmp-idecode.h m16_idecode.h
@@ -252,11 +265,56 @@ tmp-m16: $(IGEN_INSN) $(IGEN_DC) ../igen/igen $(IGEN_INCLUDE)
 	$(srcdir)/../../move-if-change tmp-model.c m16_model.c
 	$(srcdir)/../../move-if-change tmp-support.h m16_support.h
 	$(srcdir)/../../move-if-change tmp-support.c m16_support.c
-	$(srcdir)/../../move-if-change tmp-itable.h m16_itable.h
-	$(srcdir)/../../move-if-change tmp-itable.c m16_itable.c
-	$(srcdir)/../../move-if-change tmp-engine.h m16_engine.h
-	$(srcdir)/../../move-if-change tmp-engine.c m16_engine.c
-	$(srcdir)/../../move-if-change tmp-irun.c m16_irun.c
+	../igen/igen \
+		$(IGEN_TRACE) \
+		-I $(srcdir) \
+		-Werror \
+		-Wnodiscard \
+		@sim_igen_flags@ \
+		-G gen-direct-access \
+		-G gen-zero-r0 \
+		-B 32 \
+		-H 31 \
+		-i $(IGEN_INSN) \
+		-o $(IGEN_DC) \
+		-P m32_ \
+		-x \
+		-n m32_icache.h    -hc tmp-icache.h \
+		-n m32_icache.c    -c  tmp-icache.c \
+		-n m32_semantics.h -hs tmp-semantics.h \
+		-n m32_semantics.c -s  tmp-semantics.c \
+		-n m32_idecode.h   -hd tmp-idecode.h \
+		-n m32_idecode.c   -d  tmp-idecode.c \
+		-n m32_model.h     -hm tmp-model.h \
+		-n m32_model.c     -m  tmp-model.c \
+		-n m32_support.h   -hf tmp-support.h \
+		-n m32_support.c   -f  tmp-support.c \
+		#
+	$(srcdir)/../../move-if-change tmp-icache.h m32_icache.h
+	$(srcdir)/../../move-if-change tmp-icache.c m32_icache.c
+	$(srcdir)/../../move-if-change tmp-idecode.h m32_idecode.h
+	$(srcdir)/../../move-if-change tmp-idecode.c m32_idecode.c
+	$(srcdir)/../../move-if-change tmp-semantics.h m32_semantics.h
+	$(srcdir)/../../move-if-change tmp-semantics.c m32_semantics.c
+	$(srcdir)/../../move-if-change tmp-model.h m32_model.h
+	$(srcdir)/../../move-if-change tmp-model.c m32_model.c
+	$(srcdir)/../../move-if-change tmp-support.h m32_support.h
+	$(srcdir)/../../move-if-change tmp-support.c m32_support.c
+	../igen/igen \
+		$(IGEN_TRACE) \
+		-I $(srcdir) \
+		-Werror \
+		-Wnodiscard \
+		-Wnowidth \
+		@sim_igen_flags@ @sim_m16_flags@ \
+		-G gen-direct-access \
+		-G gen-zero-r0 \
+		-i $(IGEN_INSN) \
+		-n itable.h    -ht tmp-itable.h \
+		-n itable.c    -t  tmp-itable.c \
+		#
+	$(srcdir)/../../move-if-change tmp-itable.h itable.h
+	$(srcdir)/../../move-if-change tmp-itable.c itable.c
 	touch tmp-m16
 
 
diff --git a/sim/mips/configure b/sim/mips/configure
index 80b7918..46e46f1 100755
--- a/sim/mips/configure
+++ b/sim/mips/configure
@@ -1620,7 +1620,7 @@ fi
 
 
 
-# Ensure a reasonable default simulator is constructed:
+# Ensure a reasonable default simulator is constructed: (DEPRECATED)
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)        SIMCONF="-mips1 -mcpu=r1900 -mno-fp --warnings";;
@@ -1638,6 +1638,7 @@ case "${target}" in
 esac
 
 
+# DEPRECATED
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)        SIM_SUBTARGET="-DSUBTARGET_R3900=1";;
@@ -1647,6 +1648,7 @@ esac
 
 
 
+
 #
 # Select the byte order of the target
 #
@@ -1712,6 +1714,7 @@ fi
 
 
 
+
 #
 # Select the bitsize of the target
 #
@@ -1789,14 +1792,19 @@ fi
 
 
 
+
 #
 # Select the floating hardware support of the target
 #
 mips_fpu=HARDWARE_FLOATING_POINT
+mips_fpu_bitsize=
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)        mips_fpu=SOFT_FLOATING_POINT ;;
 # end-sanitize-tx19
+  mipstx39*-*-*)	mips_fpu=HARD_FLOATING_POINT
+			mips_fpu_bitsize=32
+			;;
 # start-sanitize-r5900
   mips64r59*-*-*)       mips_fpu=HARD_FLOATING_POINT ;;
 # end-sanitize-r5900
@@ -1807,7 +1815,7 @@ case "${target}" in
 esac
 
 default_sim_float="$mips_fpu"
-default_sim_float_bitsize=""
+default_sim_float_bitsize="$mips_fpu_bitsize"
 # Check whether --enable-sim-float or --disable-sim-float was given.
 if test "${enable_sim_float+set}" = set; then
   enableval="$enable_sim_float"
@@ -1835,6 +1843,7 @@ fi
 
 
 
+
 #
 # Select the level of SMP support
 #
@@ -1866,24 +1875,31 @@ fi
 
 
 
+
 #
 # Select the IGEN architecture
 #
-sim_use_gen=NO
+sim_use_gen=IGEN
 sim_igen_machine="-M mipsIV"
 sim_m16_machine="-M mips16"
 sim_igen_filter="32,64,f"
 sim_m16_filter="16"
-
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)	sim_default_gen=M16
+			#sim_use_gen=M16
+			sim_use_gen=NO
 			sim_igen_machine="-M tx19"
 			sim_m16_machine="-M tx19"
 			sim_igen_filter="32"
 			sim_m16_filter="16"
 			;;
 # end-sanitize-tx19
+  mipstx39*-*-*)	sim_default_gen=IGEN
+			sim_use_gen=IGEN
+			sim_igen_filter="32,f"
+			sim_igen_machine="-M r3900"
+			;;
 # start-sanitize-r5900
   mips64r59*-*-*)	sim_default_gen=IGEN
 			sim_use_gen=IGEN
@@ -1903,12 +1919,18 @@ case "${target}" in
 			sim_igen_machine="-M vr5000,vr5400 -G gen-multi-sim=vr5000"
 # end-sanitize-vr5400
 			;;
+  mips64*-*-*)		sim_default_gen=IGEN
+			sim_igen_filter="32,64,f"
+			sim_use_gen=IGEN
+			;;
   mips16*-*-*)		sim_default_gen=M16
+			sim_igen_filter="32,64,f"
+			sim_m16_filter="16"
+			sim_use_igen=NO
 			;;
-  mips32*-*-*)		sim_default_gen=IGEN
+  mips*-*-*)		sim_default_gen=IGEN
 			sim_igen_filter="32,f"
-			;;
-  *)                    sim_default_gen=IGEN
+			sim_use_gen=IGEN
 			;;
 esac
 sim_igen_flags="-F ${sim_igen_filter} ${sim_igen_machine} ${sim_igen_smp}"
@@ -1916,6 +1938,8 @@ sim_m16_flags=" -F ${sim_m16_filter}  ${sim_m16_machine}  ${sim_igen_smp}"
 
 
 
+
+
 #
 # Enable igen
 #
@@ -1942,17 +1966,17 @@ for ac_hdr in string.h strings.h stdlib.h stdlib.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:1946: checking for $ac_hdr" >&5
+echo "configure:1970: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1951 "configure"
+#line 1975 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1956: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1980: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -1979,7 +2003,7 @@ fi
 done
 
 echo $ac_n "checking for fabs in -lm""... $ac_c" 1>&6
-echo "configure:1983: checking for fabs in -lm" >&5
+echo "configure:2007: checking for fabs in -lm" >&5
 ac_lib_var=`echo m'_'fabs | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -1987,7 +2011,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lm  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 1991 "configure"
+#line 2015 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -1998,7 +2022,7 @@ int main() {
 fabs()
 ; return 0; }
 EOF
-if { (eval echo configure:2002: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest; then
+if { (eval echo configure:2026: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2028,12 +2052,12 @@ fi
 for ac_func in aint anint sqrt
 do
 echo $ac_n "checking for $ac_func""... $ac_c" 1>&6
-echo "configure:2032: checking for $ac_func" >&5
+echo "configure:2056: checking for $ac_func" >&5
 if eval "test \"`echo '$''{'ac_cv_func_$ac_func'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2037 "configure"
+#line 2061 "configure"
 #include "confdefs.h"
 /* System header to define __stub macros and hopefully few prototypes,
     which can conflict with char $ac_func(); below.  */
@@ -2056,7 +2080,7 @@ $ac_func();
 
 ; return 0; }
 EOF
-if { (eval echo configure:2060: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest; then
+if { (eval echo configure:2084: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest; then
   rm -rf conftest*
   eval "ac_cv_func_$ac_func=yes"
 else
diff --git a/sim/mips/configure.in b/sim/mips/configure.in
index cef211d..47f9a6a 100644
--- a/sim/mips/configure.in
+++ b/sim/mips/configure.in
@@ -85,10 +85,14 @@ SIM_AC_OPTION_BITSIZE($mips_bitsize,$mips_msb)
 # Select the floating hardware support of the target
 #
 mips_fpu=HARDWARE_FLOATING_POINT
+mips_fpu_bitsize=
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)        mips_fpu=SOFT_FLOATING_POINT ;;
 # end-sanitize-tx19
+  mipstx39*-*-*)	mips_fpu=HARD_FLOATING_POINT
+			mips_fpu_bitsize=32
+			;;
 # start-sanitize-r5900
   mips64r59*-*-*)       mips_fpu=HARD_FLOATING_POINT ;;
 # end-sanitize-r5900
@@ -97,7 +101,7 @@ case "${target}" in
   mips*-*-*)            mips_fpu=HARD_FLOATING_POINT ;;
   *)                    mips_fpu=HARD_FLOATING_POINT ;;
 esac
-SIM_AC_OPTION_FLOAT($mips_fpu)
+SIM_AC_OPTION_FLOAT($mips_fpu,$mips_fpu_bitsize)
 
 
 
@@ -117,7 +121,7 @@ SIM_AC_OPTION_SMP($mips_smp)
 #
 # Select the IGEN architecture
 #
-sim_use_gen=NO
+sim_use_gen=IGEN
 sim_igen_machine="-M mipsIV"
 sim_m16_machine="-M mips16"
 sim_igen_filter="32,64,f"
@@ -125,12 +129,19 @@ sim_m16_filter="16"
 case "${target}" in
 # start-sanitize-tx19
   mipstx19*-*-*)	sim_default_gen=M16
+			#sim_use_gen=M16
+			sim_use_gen=NO
 			sim_igen_machine="-M tx19"
 			sim_m16_machine="-M tx19"
 			sim_igen_filter="32"
 			sim_m16_filter="16"
 			;;
 # end-sanitize-tx19
+  mipstx39*-*-*)	sim_default_gen=IGEN
+			sim_use_gen=IGEN
+			sim_igen_filter="32,f"
+			sim_igen_machine="-M r3900"
+			;;
 # start-sanitize-r5900
   mips64r59*-*-*)	sim_default_gen=IGEN
 			sim_use_gen=IGEN
@@ -157,6 +168,7 @@ case "${target}" in
   mips16*-*-*)		sim_default_gen=M16
 			sim_igen_filter="32,64,f"
 			sim_m16_filter="16"
+			sim_use_igen=NO
 			;;
   mips*-*-*)		sim_default_gen=IGEN
 			sim_igen_filter="32,f"
diff --git a/sim/mips/interp.c b/sim/mips/interp.c
index 6de127a..9045004 100644
--- a/sim/mips/interp.c
+++ b/sim/mips/interp.c
@@ -339,7 +339,6 @@ sim_open (kind, cb, abfd, argv)
      registers: */
   {
     int rn;
-<<<<<<< interp.c
     for (rn = 0; (rn < (LAST_EMBED_REGNUM + 1)); rn++)
       {
 	if (rn < 32)
@@ -353,20 +352,6 @@ sim_open (kind, cb, abfd, argv)
 	else
 	  cpu->register_widths[rn] = 0;
       }
-=======
-    for (rn = 0; (rn < (LAST_EMBED_REGNUM + 1)); rn++) {
-      if (rn < 32)
-       cpu->register_widths[rn] = WITH_TARGET_WORD_BITSIZE;
-      else if ((rn >= FGRIDX) && (rn < (FGRIDX + 32)))
-       cpu->register_widths[rn] = WITH_TARGET_WORD_BITSIZE;
-      else if ((rn >= 33) && (rn <= 37))
-       cpu->register_widths[rn] = WITH_TARGET_WORD_BITSIZE;
-      else if ((rn == SRIDX) || (rn == FCR0IDX) || (rn == FCR31IDX) || ((rn >= 72) && (rn <= 89)))
-       cpu->register_widths[rn] = 32;
-      else
-       cpu->register_widths[rn] = 0;
-    }
->>>>>>> 1.94
     /* start-sanitize-r5900 */
 
     /* set the 5900 "upper" registers to 64 bits */
@@ -1580,6 +1565,29 @@ ifetch32 (SIM_DESC sd,
 }
 
 
+unsigned16
+ifetch16 (SIM_DESC sd,
+	  sim_cpu *cpu,
+	  address_word cia,
+	  address_word vaddr)
+{
+  /* Copy the action of the LW instruction */
+  address_word reverse = (ReverseEndian ? (LOADDRMASK >> 2) : 0);
+  address_word bigend = (BigEndianCPU ? (LOADDRMASK >> 2) : 0);
+  unsigned64 value;
+  address_word paddr;
+  unsigned16 instruction;
+  unsigned byte;
+  int cca;
+  AddressTranslation (vaddr, isINSTRUCTION, isLOAD, &paddr, &cca, isTARGET, isREAL);
+  paddr = ((paddr & ~LOADDRMASK) | ((paddr & LOADDRMASK) ^ (reverse << 2)));
+  LoadMemory (&value, NULL, cca, AccessLength_WORD, paddr, vaddr, isINSTRUCTION, isREAL);
+  byte = ((vaddr & LOADDRMASK) ^ (bigend << 2));
+  instruction = ((value >> (8 * byte)) & 0xFFFFFFFF);
+  return instruction;
+}
+
+
 /* Description from page A-26 of the "MIPS IV Instruction Set" manual (revision 3.1) */
 /* Order loads and stores to synchronise shared memory. Perform the
    action necessary to make the effects of groups of synchronizable