Reorganisation of the source tree

Most of the other users of the fptools build system have migrated to
Cabal, and with the move to darcs we can now flatten the source tree
without losing history, so here goes.

The main change is that the ghc/ subdir is gone, and most of what it
contained is now at the top level.  The build system now makes no
pretense at being multi-project, it is just the GHC build system.

No doubt this will break many things, and there will be a period of
instability while we fix the dependencies.  A straightforward build
should work, but I haven't yet fixed binary/source distributions.
Changes to the Building Guide will follow, too.

1 files changed, 141 insertions, 0 deletions

diff --git a/rts/gmp/mpn/x86/k6/cross.pl b/rts/gmp/mpn/x86/k6/cross.pl
new file mode 100644
index 0000000000..21734f3e52
--- /dev/null
+++ b/rts/gmp/mpn/x86/k6/cross.pl
@@ -0,0 +1,141 @@
+#! /usr/bin/perl
+
+# Copyright (C) 2000 Free Software Foundation, Inc.
+#
+# This file is part of the GNU MP Library.
+#
+# The GNU MP Library is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation; either version 2.1 of the License, or (at
+# your option) any later version.
+#
+# The GNU MP Library is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+# License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
+# the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+# MA 02111-1307, USA.
+
+
+# Usage: cross.pl [filename.o]...
+#
+# Produce an annotated disassembly of the given object files, indicating
+# certain code alignment and addressing mode problems afflicting K6 chips.
+# "ZZ" is used on all annotations, so this can be searched for.
+#
+# 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.
+#
+# Bugs:
+#
+# Instructions without mod/rm bytes or which are already vector decoded are
+# unaffected by cache line boundary crossing, but not all of these have yet
+# been put in as exceptions.  All that occur in practice in GMP are present
+# though.
+#
+# There's no messages for using the vector decoded addressing mode (%esi),
+# but that mode is easy to avoid when coding.
+
+use strict;
+
+sub disassemble {
+    my ($file) = @_;
+    my ($addr,$b1,$b2,$b3, $prefix,$opcode,$modrm);
+
+    open (IN, "objdump -Srfh $file |")
+	|| die "Cannot open pipe from objdump\n";
+    while (<IN>) {
+	print;
+
+	if (/^[ \t]*[0-9]+[ \t]+\.text[ \t]/ && /2\*\*([0-9]+)$/) {
+	    if ($1 < 5) {
+		print "ZZ need at least 2**5 for predictable cache line crossing\n";
+	    }
+	}
+	
+	if (/^[ \t]*([0-9a-f]*):[ \t]*([0-9a-f]+)[ \t]+([0-9a-f]+)[ \t]+([0-9a-f]+)/) {
+	    ($addr,$b1,$b2,$b3) = ($1,$2,$3,$4);
+
+	} elsif (/^[ \t]*([0-9a-f]*):[ \t]*([0-9a-f]+)[ \t]+([0-9a-f]+)/) {
+	    ($addr,$b1,$b2,$b3) = ($1,$2,$3,'');
+
+	} elsif (/^[ \t]*([0-9a-f]*):[ \t]*([0-9a-f]+)/) {
+	    ($addr,$b1,$b2,$b3) = ($1,$2,'','');
+
+	} else {
+	    next;
+	}
+
+	if ($b1 =~ /0f/) {
+	    $prefix = $b1;
+	    $opcode = $b2;
+	    $modrm = $b3;
+	} else {
+	    $prefix = '';
+	    $opcode = $b1;
+	    $modrm = $b2;
+	}
+
+	# modrm of the form 00-xxx-100 with an 0F prefix is the problem case
+	# for K6 and pre-CXT K6-2
+	if ($prefix =~ /0f/
+	    && $opcode !~ /^8/         # jcond disp32
+	    && $modrm =~ /^[0-3][4c]/) {
+	    print "ZZ ($file) >3 bytes to determine instruction length\n";
+	}
+
+	# with just an opcode, starting 1f mod 20h
+	if ($addr =~ /[13579bdf]f$/
+	    && $prefix !~ /0f/
+	    && $opcode !~ /1[012345]/ # adc
+	    && $opcode !~ /1[89abcd]/ # sbb
+	    && $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 !~ /e[0123]/   # loop/loopz/loopnz/jcxz
+	    && $opcode !~ /e[b9]/     # jmp disp8/disp32
+	    && $opcode !~ /f[89abcd]/ # clc,stc,cli,sti,cld,std
+	    && !($opcode =~ /f[67]/          # grp 1
+		 && $modrm =~ /^[2367abef]/) # mul, imul, div, idiv
+	    && $modrm !~ /^$/) {
+	    print "ZZ ($file) opcode/modrm cross 32-byte boundary\n";
+	}
+
+	# with an 0F prefix, anything starting at 1f mod 20h
+	if ($addr =~ /[13579bdf][f]$/
+	    && $prefix =~ /0f/) {
+	    print "ZZ ($file) prefix/opcode cross 32-byte boundary\n";
+	}
+
+	# with an 0F prefix, anything with mod/rm starting at 1e mod 20h
+	if ($addr =~ /[13579bdf][e]$/
+	    && $prefix =~ /0f/
+	     && $opcode !~ /^8/        # jcond disp32
+	    && $modrm !~ /^$/) {
+	    print "ZZ ($file) prefix/opcode/modrm cross 32-byte boundary\n";
+	}
+    }
+    close IN || die "Error from objdump (or objdump not available)\n";
+}
+
+
+my @files;
+if ($#ARGV >= 0) {
+    @files = @ARGV;
+} else {
+    @files = glob "*.asm";
+    map {s/.asm/.o/} @files;
+}
+
+foreach (@files)  {
+    disassemble($_);
+}