===================================================================
RCS file: /home/cvs/OpenXM_contrib/gmp/mpn/x86/k6/Attic/cross.pl,v
retrieving revision 1.1
retrieving revision 1.1.1.2
diff -u -p -r1.1 -r1.1.1.2
--- OpenXM_contrib/gmp/mpn/x86/k6/Attic/cross.pl	2000/09/09 14:12:42	1.1
+++ OpenXM_contrib/gmp/mpn/x86/k6/Attic/cross.pl	2003/08/25 16:06:27	1.1.1.2
@@ -1,6 +1,6 @@
 #! /usr/bin/perl
 
-# Copyright (C) 2000 Free Software Foundation, Inc.
+# Copyright 2000, 2001 Free Software Foundation, Inc.
 #
 # This file is part of the GNU MP Library.
 #
@@ -29,10 +29,17 @@
 # With no arguments, all .o files corresponding to .asm files are processed.
 # This is good in the mpn object directory of a k6*-*-* build.
 #
-# As far as fixing problems goes, any cache line crossing problems in loops
-# get attention, but as a rule it's too tedious to rearrange code or slip in
-# nops to fix every problem in setup or finishup code.
+# Code alignments of 8 bytes or more are handled.  When 32 is used, cache
+# line boundaries will fall in at offsets 0x20,0x40,etc and problems are
+# flagged at those locations.  When 16 is used, the line boundaries can also
+# fall at offsets 0x10,0x30,0x50,etc, depending where the file is loaded, so
+# problems are identified there too.  Likewise when 8 byte alignment is used
+# problems are flagged additionally at 0x08,0x18,0x28,etc.
 #
+# Usually 32 byte alignment is used for k6 routines, but less is certainly
+# possible if through good luck, or a little tweaking, cache line crossing
+# problems can be avoided at the extra locations.
+#
 # Bugs:
 #
 # Instructions without mod/rm bytes or which are already vector decoded are
@@ -41,13 +48,19 @@
 # though.
 #
 # There's no messages for using the vector decoded addressing mode (%esi),
-# but that mode is easy to avoid when coding.
+# but that's easy to avoid when coding.
+#
+# Future:
+#
+# Warn about jump targets that are poorly aligned (less than 2 instructions
+# before a cache line boundary).
 
 use strict;
 
 sub disassemble {
     my ($file) = @_;
     my ($addr,$b1,$b2,$b3, $prefix,$opcode,$modrm);
+    my $align;
 
     open (IN, "objdump -Srfh $file |")
 	|| die "Cannot open pipe from objdump\n";
@@ -55,8 +68,10 @@ sub disassemble {
 	print;
 
 	if (/^[ \t]*[0-9]+[ \t]+\.text[ \t]/ && /2\*\*([0-9]+)$/) {
-	    if ($1 < 5) {
-		print "ZZ need at least 2**5 for predictable cache line crossing\n";
+	    $align = 1 << $1;
+	    if ($align < 8) {
+		print "ZZ cross.pl cannot handle alignment < 2**3\n";
+		$align = 8
 	    }
 	}
 	
@@ -88,21 +103,27 @@ sub disassemble {
 	if ($prefix =~ /0f/
 	    && $opcode !~ /^8/         # jcond disp32
 	    && $modrm =~ /^[0-3][4c]/) {
-	    print "ZZ ($file) >3 bytes to determine instruction length\n";
+	    print "ZZ ($file) >3 bytes to determine instruction length [K6]\n";
 	}
 
 	# with just an opcode, starting 1f mod 20h
-	if ($addr =~ /[13579bdf]f$/
+	if (($align==32 && $addr =~ /[13579bdf]f$/
+	     || $align==16 && $addr =~ /f$/
+	     || $align==8 && $addr =~ /[7f]$/)
 	    && $prefix !~ /0f/
 	    && $opcode !~ /1[012345]/ # adc
 	    && $opcode !~ /1[89abcd]/ # sbb
+	    && $opcode !~ /^4/        # inc/dec reg
+	    && $opcode !~ /^5/        # push/pop reg
 	    && $opcode !~ /68/        # push $imm32
 	    && $opcode !~ /^7/        # jcond disp8
 	    && $opcode !~ /a[89]/     # test+imm
 	    && $opcode !~ /a[a-f]/    # stos/lods/scas
 	    && $opcode !~ /b8/        # movl $imm32,%eax
+	    && $opcode !~ /d[0123]/   # rcl
 	    && $opcode !~ /e[0123]/   # loop/loopz/loopnz/jcxz
-	    && $opcode !~ /e[b9]/     # jmp disp8/disp32
+	    && $opcode !~ /e8/        # call disp32
+	    && $opcode !~ /e[9b]/     # jmp disp32/disp8
 	    && $opcode !~ /f[89abcd]/ # clc,stc,cli,sti,cld,std
 	    && !($opcode =~ /f[67]/          # grp 1
 		 && $modrm =~ /^[2367abef]/) # mul, imul, div, idiv
@@ -111,15 +132,26 @@ sub disassemble {
 	}
 
 	# with an 0F prefix, anything starting at 1f mod 20h
-	if ($addr =~ /[13579bdf][f]$/
-	    && $prefix =~ /0f/) {
+	if (($align==32 && $addr =~ /[13579bdf][f]$/
+	     || $align==16 && $addr =~ /f$/
+	     || $align==8 && $addr =~ /[7f]$/)
+	    && $prefix =~ /0f/
+	    && $opcode !~ /af/        # imul
+	    && $opcode !~ /a[45]/     # shldl
+	    && $opcode !~ /a[cd]/     # shrdl
+	    ) {
 	    print "ZZ ($file) prefix/opcode cross 32-byte boundary\n";
 	}
 
 	# with an 0F prefix, anything with mod/rm starting at 1e mod 20h
-	if ($addr =~ /[13579bdf][e]$/
+	if (($align==32 && $addr =~ /[13579bdf][e]$/
+	     || $align==16 && $addr =~ /[e]$/
+	     || $align==8 && $addr =~ /[6e]$/)
 	    && $prefix =~ /0f/
 	     && $opcode !~ /^8/        # jcond disp32
+	     && $opcode !~ /af/        # imull reg,reg
+	     && $opcode !~ /a[45]/     # shldl
+	     && $opcode !~ /a[cd]/     # shrdl
 	    && $modrm !~ /^$/) {
 	    print "ZZ ($file) prefix/opcode/modrm cross 32-byte boundary\n";
 	}