First batch of file additions for cross-compiler:

	new file:   ghc/ghc-cross.wrapper
	new file:   includes/mkDerivedConstants.cross.awk
	new file:   includes/mkSizeMacros.cross.awk
	new file:   rules/cross-compiling.mk

These are expected to sit quietly in the tree until
the rest of the machinery matures on an (upcoming)
branch. Reviews will begin to make sense as soon as
that has happened. Anyway, comments are welcome. See
<http://www.haskell.org/pipermail/cvs-ghc/2012-July/074456.html>
for background.

Disclaimer: these source files are not (yet) up to the
            quality standards set by the rest of the tree.

Cleanups, move-arounds and rewrites (i.e. .awk -> .hs), as
well as additional comments and documentation will happen
as soon as the basic functionality of a cross-compiler is
working reliably.

4 files changed, 457 insertions, 0 deletions

diff --git a/ghc/ghc-cross.wrapper b/ghc/ghc-cross.wrapper
new file mode 100644
index 0000000000..56564e589d
--- /dev/null
+++ b/ghc/ghc-cross.wrapper
@@ -0,0 +1 @@
+exec "$executablename" -B"$topdir" ${1+"$@"} -pgma "$pgmgcc" -pgmc "$pgmgcc" -pgml "$pgmgcc"
diff --git a/includes/mkDerivedConstants.cross.awk b/includes/mkDerivedConstants.cross.awk
new file mode 100644
index 0000000000..c66655e922
--- /dev/null
+++ b/includes/mkDerivedConstants.cross.awk
@@ -0,0 +1,350 @@
+## This script rewrites normal C structs into successively
+## greater ones so that field offset computation becomes a
+## sizeof lookup and thus amenable to compile-time computations.
+
+## Usage: pipe stg/Regs.h into 'awk' running this script
+##        to obtain a .c file that can be compiled to .o
+##        with the gcc from the cross toolchain. Then
+##        use another 'awk' script to process the 'nm'
+##        output of the object file.
+
+## Motivation: since in general we can not run executables
+##             created by the cross toolchain, we need another
+##             way of finding out field offsets and type sizes
+##             of the target platform.
+
+BEGIN {
+  interesting = 0
+  seed = 0
+  print "/* this file is generated by mkDerivedConstants.cross.awk, do not touch */"
+  print "/* needs to be compiled with the target gcc */"
+  print ""
+  print "#include \"Rts.h\""
+  print "#include \"Capability.h\""
+  print ""
+  ## these do not have a proper typedef; supply them here
+  print "#define FLAG_STRUCT_TYPE(IT) typedef struct IT ## _FLAGS IT ## _FLAGS"
+  print "FLAG_STRUCT_TYPE(GC);"
+  print "FLAG_STRUCT_TYPE(DEBUG);"
+  print "FLAG_STRUCT_TYPE(COST_CENTRE);"
+  print "FLAG_STRUCT_TYPE(PROFILING);"
+  print "FLAG_STRUCT_TYPE(TRACE);"
+  print "FLAG_STRUCT_TYPE(CONCURRENT);"
+  print "FLAG_STRUCT_TYPE(MISC);"
+  print "FLAG_STRUCT_TYPE(PAR);"
+  print "FLAG_STRUCT_TYPE(TICKY);"
+  ## these we do know how to get the field size,
+  ## so do not bother mining it
+  print "#define DO_NOT_MINE_UNION_MEMBER(STRUCT, NESTED_MEMBER, ID) char nestedfieldsize$ ## STRUCT ## $ ## ID [sizeof ((STRUCT*)0)->NESTED_MEMBER]"
+  print "DO_NOT_MINE_UNION_MEMBER(StgHeader, prof.hp.ldvw, prof_hp_ldvw);"
+  print "DO_NOT_MINE_UNION_MEMBER(StgFunInfoExtraFwd, b.bitmap, b_bitmap);"
+  print "DO_NOT_MINE_UNION_MEMBER(StgFunInfoExtraRev, b.bitmap, b_bitmap);"
+}
+
+## pass through embedded unions
+eat_union && /^[ \t]*}[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t]*;[ \t]*$/ {
+  sub(/^[ \t]*}[ \t]*/, "")
+  sub(/[ \t]*;[ \t]*$/, "")
+  new_offset_struct_name = struct_name $0
+  print ""
+
+  eat_union = 0
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " $0 ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " $0 ") ? 1 : -1];"
+  }
+
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+eat_union {
+  next
+}
+
+/# [0-9]* "rts\// {
+  ours = 1
+  next
+}
+
+/# [0-9]* "includes\// {
+  ours = 1
+  next
+}
+
+## filter out non-ghc headers
+/# [0-9]* "/ {
+  ours = 0
+  next
+}
+
+!ours {
+  next
+}
+
+!interesting {
+  struct_name = "$" seed "$"
+  offset_struct_name = ""
+  known_struct_name = ""
+  eat_union = 0
+  assumptions = ""
+}
+
+## kill empty line
+/^[ \t]*$/ {
+  next
+}
+
+/^# [0-9]/ {
+  print
+  next
+}
+
+/^typedef struct[ \t][ \t]*[_0-9a-zA-Z]*[ \t]*{[ \t]*$/ {
+  if (interesting) error "previous struct not closed?"
+  interesting = 1
+  print ""
+  print "/* ### Creating offset structs for " $3 " ### */"
+  next
+}
+
+/^struct[ \t][ \t]*[_0-9a-zA-Z]*[ \t]*{[ \t]*$/ {
+  if (interesting) error "previous struct not closed?"
+  interesting = 1
+  known_struct_name = $2
+  sub(/_$/, "", known_struct_name);
+  print ""
+  print "/* ### Creating offset structs for " known_struct_name " ### */"
+  print "char associate$" known_struct_name "$" seed ";"
+  next
+}
+
+## end of struct
+##
+interesting && /^[ \t]*}[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t]*;[ \t]*$/{
+  sub(/;$/, "", $2)
+
+  print "char associate$" $2 "$" seed ";"
+  print "char SIZEOF$" seed "[sizeof(" $2 ")];"
+  print ""
+  print ""
+  gsub(/\^\^\^/, $2, assumptions);
+  print assumptions
+  ++seed
+  interesting = 0
+  next
+}
+
+## Ptr-typedef
+interesting && /^[ \t]*}[ \t]*\*[_0-9a-zA-Z][_0-9a-zA-Z]*Ptr[ \t]*;[ \t]*$/{
+  sub(/Ptr;$/, "", $2)
+  sub(/^\*/, "", $2)
+
+  print "char associate$" $2 "$" seed ";"
+  print "char SIZEOF$" seed "[sizeof(" $2 ")];"
+  print ""
+  print ""
+  gsub(/\^\^\^/, $2, assumptions);
+  print assumptions
+  ++seed
+  interesting = 0
+  next
+}
+
+interesting && /^[ \t]*}[; \t]*$/ {
+  print "char SIZEOF$" seed "[sizeof(" known_struct_name ")];"
+  print ""
+  print ""
+  gsub(/\^\^\^/, known_struct_name, assumptions);
+  print assumptions
+  ++seed
+  interesting = 0
+}
+
+# collapse whitespace after '*'
+interesting {
+  # normalize some types
+  sub(/struct StgClosure_[ \t]*\*/, "StgClosure *")
+  gsub(/\*[ \t]*volatile/, "*")
+  # group stars together
+  gsub(/\*[ \t]*/, "*")
+  sub(/\*/, " *")
+  print "//   " $0
+  # remove volatile
+  sub(/[ \t]volatile[ \t]/, " ")
+  # remove const
+  sub(/[ \t]const[ \t]/, " ")
+}
+
+## (pointer to struct) member of struct
+##
+interesting && /^[ \t]*struct[ \t][ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t]*\*[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t]*;[ \t]*$/ {
+  if (!$4) {
+    sub(/^\*/, "", $3)
+    $4 = $3
+  }
+  sub(/;$/, "", $4)
+
+  new_offset_struct_name = struct_name $4
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " $4 ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " $4 ") ? 1 : -1];"
+  }
+  print "char fieldsize" new_offset_struct_name "[sizeof(struct " $2 "*)];"
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+## (simple pointer) member of struct
+##
+interesting && /^[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*\*\**[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t]*;[ \t]*$/ {
+  sub(/;$/, "", $2)
+  sub(/^\**/, "", $2)
+
+  new_offset_struct_name = struct_name $2
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " $2 ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " $2 ") ? 1 : -1];"
+  }
+  print "char fieldsize" new_offset_struct_name "[sizeof(" $1 "*)];"
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+## member of struct
+##
+interesting && /^[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*;[ \t]*$/ {
+  sub(/;$/, "", $2)
+
+  new_offset_struct_name = struct_name $2
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " $2 ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " $2 ") ? 1 : -1];"
+  }
+  print "char fieldsize" new_offset_struct_name "[sizeof(" $1 ")];"
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+## struct member of struct
+##
+interesting && /^[ \t]*struct[ \t][ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*;[ \t]*$/ {
+  sub(/;$/, "", $3)
+
+  new_offset_struct_name = struct_name $3
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " $3 ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " $3 ") ? 1 : -1];"
+  }
+  print "char fieldsize" new_offset_struct_name "[sizeof(struct " $2 ")];"
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+## embedded union
+interesting && /^[ \t]*union[ \t]*{[ \t]*$/ {
+  eat_union = 1
+  next
+}
+
+## array member
+interesting && /^[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*\**[_0-9a-zA-Z][_0-9a-zA-Z]*\[.*\];[ \t]*$/ {
+  sub(/;[ \t]*$/, "", $0)
+
+  full = $0
+  sub(/^[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*/, "", full)
+  split(full, parts, "[")
+  mname = parts[1]
+  sub(/^\**/, "", mname)
+
+  new_offset_struct_name = struct_name mname
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " mname ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " mname ") ? 1 : -1];"
+  }
+
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+
+## padded member of struct
+##   of this form: StgHalfInt slow_apply_offset; StgHalfWord __pad_slow_apply_offset;;
+##
+interesting && /^[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*;[ \t]*[_0-9a-zA-Z][_0-9a-zA-Z]*[ \t][ \t]*__pad_[a-zA-Z][_0-9a-zA-Z]*;;*[ \t]*$/ {
+  mname = $2
+  sub(/;$/, "", mname)
+
+  new_offset_struct_name = struct_name mname
+  print ""
+
+  if (!offset_struct_name)
+  {
+    print "char starting" new_offset_struct_name "[2];"
+  }
+  else
+  {
+    assumptions = assumptions "\n" "char sizeof" new_offset_struct_name "[offsetof(^^^, " mname ")];"
+    assumptions = assumptions "\n" "typedef char verify_size" new_offset_struct_name "[sizeof sizeof" new_offset_struct_name " == offsetof(^^^, " mname ") ? 1 : -1];"
+  }
+  print ""
+  print ""
+  offset_struct_name = new_offset_struct_name
+  next
+}
+
+interesting && /;[ \t]*$/ {
+  print "Member not recognized: " $0 > "/dev/stderr"
+  exit 1
+}
\ No newline at end of file
diff --git a/includes/mkSizeMacros.cross.awk b/includes/mkSizeMacros.cross.awk
new file mode 100644
index 0000000000..e33e4ff4e5
--- /dev/null
+++ b/includes/mkSizeMacros.cross.awk
@@ -0,0 +1,82 @@
+BEGIN {
+  print "#define OFFSET(s_type, field) OFFSET_ ## s_type ## _ ## field"
+  print "#define FIELD_SIZE(s_type, field) FIELD_SIZE_ ## s_type ## _ ## field"
+  print "#define TYPE_SIZE(type) TYPE_SIZE_ ## type"
+  print ""
+}
+
+/^0[0-9a-zA-Z]* C _*associate\$/ {
+  sub(/_*associate\$/, "", $3)
+  split($3, arr, "$")
+  assoc[arr[2]] = arr[1]
+  next
+}
+
+/^00*2 C _*starting\$[0-9]*\$[_0-9a-zA-Z]*$/ {
+  sub(/_*starting\$/, "", $3)
+  split($3, arr, "$")
+  sub(/^0*/, "", $1)
+  print "#define OFFSET_" assoc[arr[1]] "_" arr[2] " 0x0"
+  next
+}
+
+/^0[0-9a-zA-Z]* C _*sizeof\$[0-9]*\$[_0-9a-zA-Z]*$/ {
+  sub(/_*sizeof\$/, "", $3)
+  split($3, arr, "$")
+  sub(/^0*/, "", $1)
+  print "#define OFFSET_" assoc[arr[1]] "_" arr[2] " 0x" $1
+  next
+}
+
+/^0[0-9a-zA-Z]* C _*fieldsize\$[0-9]*\$[_0-9a-zA-Z]*$/ {
+  sub(/_*fieldsize\$/, "", $3)
+  split($3, arr, "$")
+  sub(/^0*/, "", $1)
+  print "#define FIELD_SIZE_" assoc[arr[1]] "_" arr[2] " 0x" $1 "UL"
+  next
+}
+
+/^0[0-9a-zA-Z]* C _*nestedfieldsize\$[_0-9a-zA-Z]*\$[_0-9a-zA-Z]*$/ {
+  sub(/_*nestedfieldsize\$/, "", $3)
+  split($3, arr, "$")
+  sub(/^0*/, "", $1)
+  print "#define FIELD_SIZE_" arr[1] "_" arr[2] " 0x" $1 "UL"
+  next
+}
+
+/^0[0-9a-zA-Z]* C _*SIZEOF\$[0-9]*$/ {
+  sub(/_*SIZEOF\$/, "", $3)
+  sub(/^0*/, "", $1)
+  print "#define TYPE_SIZE_" assoc[$3] " 0x" $1
+  next
+}
+
+{ print "// " $0 }
+
+END {
+    ## some indirect offsets
+    print "#define OFFSET_StgHeader_prof_ccs (OFFSET_StgHeader_prof + OFFSET_StgProfHeader_ccs)"
+    print "#define OFFSET_StgHeader_prof_hp_ldvw (OFFSET_StgHeader_prof + OFFSET_StgProfHeader_hp + 0)"
+    print "#define OFFSET_StgTSO_prof_cccs (OFFSET_StgTSO_prof + OFFSET_StgTSOProfInfo_cccs)"
+    print "#define OFFSET_RTS_FLAGS_ProfFlags_showCCSOnException (OFFSET_RTS_FLAGS_ProfFlags + OFFSET_PROFILING_FLAGS_showCCSOnException)"
+
+
+    print "#define OFFSET_RTS_FLAGS_DebugFlags_apply (OFFSET_RTS_FLAGS_DebugFlags + OFFSET_DEBUG_FLAGS_apply)"
+    print "#define OFFSET_RTS_FLAGS_DebugFlags_sanity (OFFSET_RTS_FLAGS_DebugFlags + OFFSET_DEBUG_FLAGS_sanity)"
+    print "#define OFFSET_RTS_FLAGS_DebugFlags_weak (OFFSET_RTS_FLAGS_DebugFlags + OFFSET_DEBUG_FLAGS_weak)"
+    print "#define OFFSET_RTS_FLAGS_GcFlags_initialStkSize (OFFSET_RTS_FLAGS_GcFlags + OFFSET_GC_FLAGS_initialStkSize)"
+    print "#define OFFSET_RTS_FLAGS_MiscFlags_tickInterval (OFFSET_RTS_FLAGS_MiscFlags + OFFSET_MISC_FLAGS_tickInterval)"
+
+    print "#define OFFSET_StgFunInfoExtraFwd_b_bitmap (OFFSET_StgFunInfoExtraFwd_b + 0)"
+    print "#define OFFSET_StgFunInfoExtraRev_b_bitmap (OFFSET_StgFunInfoExtraRev_b + 0)"
+
+    ## some indirect field sizes
+    print "#define FIELD_SIZE_StgHeader_prof_ccs FIELD_SIZE_StgProfHeader_ccs"
+    print "#define FIELD_SIZE_StgTSO_prof_cccs FIELD_SIZE_StgTSOProfInfo_cccs"
+    print "#define FIELD_SIZE_RTS_FLAGS_ProfFlags_showCCSOnException FIELD_SIZE_PROFILING_FLAGS_showCCSOnException"
+    print "#define FIELD_SIZE_RTS_FLAGS_DebugFlags_apply FIELD_SIZE_DEBUG_FLAGS_apply"
+    print "#define FIELD_SIZE_RTS_FLAGS_DebugFlags_sanity FIELD_SIZE_DEBUG_FLAGS_sanity"
+    print "#define FIELD_SIZE_RTS_FLAGS_DebugFlags_weak FIELD_SIZE_DEBUG_FLAGS_weak"
+    print "#define FIELD_SIZE_RTS_FLAGS_GcFlags_initialStkSize FIELD_SIZE_GC_FLAGS_initialStkSize"
+    print "#define FIELD_SIZE_RTS_FLAGS_MiscFlags_tickInterval FIELD_SIZE_MISC_FLAGS_tickInterval"
+}
diff --git a/rules/cross-compiling.mk b/rules/cross-compiling.mk
new file mode 100644
index 0000000000..9f9ec6f542
--- /dev/null
+++ b/rules/cross-compiling.mk
@@ -0,0 +1,24 @@
+# -----------------------------------------------------------------------------
+#
+# (c) 2012 The University of Glasgow
+#
+# This file is part of the GHC build system.
+#
+# To understand how the build system works and how to modify it, see
+#      http://hackage.haskell.org/trac/ghc/wiki/Building/Architecture
+#      http://hackage.haskell.org/trac/ghc/wiki/Building/Modifying
+#
+# -----------------------------------------------------------------------------
+
+define cross-compiling # $1 = then, $2 = else, $3 = then, ...
+ifneq "$(TARGETPLATFORM)" "$(HOSTPLATFORM)"
+ifneq "$(BUILDPLATFORM)" "$(HOSTPLATFORM)"
+$(warning When cross-compiling, the build and host platforms must be equal (--build=$(BUILDPLATFORM) --host=$(HOSTPLATFORM) --target=$(TARGETPLATFORM)))
+endif
+$1
+$3
+else
+$2
+$4
+endif
+endef