Add --rosegment option to BFD linker to stop the '-z separate-code' from generating two read-only segments.

  PR 30907

1 files changed, 100 insertions, 18 deletions

diff --git a/ld/scripttempl/elf.sc b/ld/scripttempl/elf.sc
index d5022fa..f1a61e7 100644
--- a/ld/scripttempl/elf.sc
+++ b/ld/scripttempl/elf.sc
@@ -80,6 +80,8 @@
 #		for standard sections, without initial "." or suffixes.
 #       SYMBOL_ABI_ALIGNMENT - minimum alignment in bytes which needs to be
 #               applied to every symbol definition
+#       ALL_TEXT_BEFORE_RO - put all code sections before read-only
+#               sections
 #
 # When adding sections, do note that the names of some sections are used
 # when specifying the start address of the next.
@@ -367,6 +369,11 @@ SHLIB_TEXT_START_ADDR="SEGMENT_START(\"text-segment\", ${SHLIB_TEXT_START_ADDR:-
 # between .plt and .text.
 if test -z "$TINY_READONLY_SECTION"; then
   case "$LD_FLAG" in
+    *ro*textonly*)
+      ALL_TEXT_BEFORE_RO=" "
+      SEPARATE_TEXT=" "
+      TEXT_SEGMENT_ALIGN=
+      ;;
     *textonly*)
       SEPARATE_TEXT=" "
       TEXT_SEGMENT_ALIGN=". = ALIGN(${MAXPAGESIZE});"
@@ -387,6 +394,11 @@ else
    test -z "${TEXT_BASE_ADDRESS}" && TEXT_BASE_ADDRESS="${TEXT_START_ADDR}"
 fi
 
+# ===========================================================================
+# Functions for generating parts of the linker script
+
+emit_header()
+{
 cat <<EOF
 /* Copyright (C) 2014-2024 Free Software Foundation, Inc.
 
@@ -406,14 +418,8 @@ ${RELOCATING- /* For some reason, the Solaris linker makes bad executables
   if gld -r is used and the intermediate file has sections starting
   at non-zero addresses.  Could be a Solaris ld bug, could be a GNU ld
   bug.  But for now assigning the zero vmas works.  */}
-
-SECTIONS
-{
-  ${RELOCATING+${SEPARATE_TEXT-/* Read-only sections, merged into text segment: */}}
-  ${CREATE_SHLIB-${CREATE_PIE-${RELOCATING+PROVIDE (__executable_start = ${TEXT_START_ADDR}); . = ${TEXT_BASE_ADDRESS};}}}
-  ${CREATE_SHLIB+${RELOCATING+. = ${SHLIB_TEXT_START_ADDR}${SIZEOF_HEADERS_CODE};}}
-  ${CREATE_PIE+${RELOCATING+PROVIDE (__executable_start = ${SHLIB_TEXT_START_ADDR}); . = ${SHLIB_TEXT_START_ADDR}${SIZEOF_HEADERS_CODE};}}
 EOF
+}
 
 emit_early_ro()
 {
@@ -423,10 +429,21 @@ emit_early_ro()
 EOF
 }
 
-test -n "${SEPARATE_CODE}" || emit_early_ro
+emit_executable_start()
+{
+cat <<EOF
+  ${RELOCATING+${SEPARATE_TEXT-/* Read-only sections, merged into text segment: */}}
+  ${CREATE_SHLIB-${CREATE_PIE-${RELOCATING+PROVIDE (__executable_start = ${TEXT_START_ADDR}); . = ${TEXT_BASE_ADDRESS};}}}
+  ${CREATE_SHLIB+${RELOCATING+. = ${SHLIB_TEXT_START_ADDR}${SIZEOF_HEADERS_CODE};}}
+  ${CREATE_PIE+${RELOCATING+PROVIDE (__executable_start = ${SHLIB_TEXT_START_ADDR}); . = ${SHLIB_TEXT_START_ADDR}${SIZEOF_HEADERS_CODE};}}
+EOF
+}
 
+emit_dyn()
+{
 test -n "${RELOCATING+0}" || unset NON_ALLOC_DYN
 test -z "${NON_ALLOC_DYN}" || TEXT_DYNAMIC=
+
 cat > ldscripts/dyntmp.$$ <<EOF
   ${TEXT_DYNAMIC+${DYNAMIC}}
   .hash         ${RELOCATING-0} : { *(.hash) }
@@ -443,6 +460,7 @@ if [ "x$COMBRELOC" = x ]; then
 else
   COMBRELOCCAT="cat > $COMBRELOC"
 fi
+
 eval $COMBRELOCCAT <<EOF
   ${INITIAL_RELOC_SECTIONS}
   .rel.init     ${RELOCATING-0} : { *(.rel.init) }
@@ -518,8 +536,6 @@ cat >> ldscripts/dyntmp.$$ <<EOF
   ${OTHER_PLT_RELOC_SECTIONS}
 EOF
 
-emit_dyn()
-{
   if test -z "${NO_REL_RELOCS}${NO_RELA_RELOCS}"; then
     cat ldscripts/dyntmp.$$
   else
@@ -530,17 +546,24 @@ emit_dyn()
       sed -e '/^[	 ]*\.rel\.[^}]*$/,/}/d;/^[	 ]*\.rel\./d;/__rel_iplt_/d' ldscripts/dyntmp.$$
     fi
   fi
+  
   rm -f ldscripts/dyntmp.$$
+  
   if test -n "${HAVE_DT_RELR}"; then
     echo "  .relr.dyn : { *(.relr.dyn) }"
   fi
 }
 
-test -n "${NON_ALLOC_DYN}${SEPARATE_CODE}" || emit_dyn
-
+align_text()
+{
 cat <<EOF
   ${RELOCATING+${TEXT_SEGMENT_ALIGN}}
+EOF
+}
 
+emit_text()
+{
+cat <<EOF
   .init         ${RELOCATING-0}${RELOCATING+${INIT_ADDR}} :
   {
     ${RELOCATING+${INIT_START}}
@@ -549,7 +572,9 @@ cat <<EOF
   } ${FILL}
 
   ${TEXT_PLT+${PLT_NEXT_DATA-${PLT} ${OTHER_PLT_SECTIONS}}}
+  
   ${TINY_READONLY_SECTION}
+  
   .text         ${RELOCATING-0} :
   {
     ${RELOCATING+${TEXT_START_SYMBOLS}}
@@ -563,19 +588,25 @@ cat <<EOF
     *(.gnu.warning)
     ${RELOCATING+${OTHER_TEXT_SECTIONS}}
   } ${FILL}
+  
   .fini         ${RELOCATING-0}${RELOCATING+${FINI_ADDR}} :
   {
     ${RELOCATING+${FINI_START}}
     KEEP (*(SORT_NONE(.fini)))
     ${RELOCATING+${FINI_END}}
   } ${FILL}
+  
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT-PROVIDE (__${ETEXT_NAME} = .);}}
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT-PROVIDE (_${ETEXT_NAME} = .);}}
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT-PROVIDE (${ETEXT_NAME} = .);}}
   ${RELOCATING+${TEXT_SEGMENT_ALIGN}}
 EOF
+}
 
+align_rodata()
+{
 if test -n "${SEPARATE_CODE}${SEPARATE_TEXT}"; then
+
   if test -n "${RODATA_ADDR}"; then
     RODATA_ADDR="\
 SEGMENT_START(\"rodata-segment\", ${RODATA_ADDR}) + SIZEOF_HEADERS"
@@ -583,6 +614,7 @@ SEGMENT_START(\"rodata-segment\", ${RODATA_ADDR}) + SIZEOF_HEADERS"
     RODATA_ADDR="ALIGN(${SEGMENT_SIZE}) + (. & (${MAXPAGESIZE} - 1))"
     RODATA_ADDR="SEGMENT_START(\"rodata-segment\", ${RODATA_ADDR})"
   fi
+  
   if test -n "${SHLIB_RODATA_ADDR}"; then
     SHLIB_RODATA_ADDR="\
 SEGMENT_START(\"rodata-segment\", ${SHLIB_RODATA_ADDR}) + SIZEOF_HEADERS"
@@ -590,6 +622,7 @@ SEGMENT_START(\"rodata-segment\", ${SHLIB_RODATA_ADDR}) + SIZEOF_HEADERS"
     SHLIB_RODATA_ADDR="ALIGN(${SEGMENT_SIZE}) + (. & (${MAXPAGESIZE} - 1))"
     SHLIB_RODATA_ADDR="SEGMENT_START(\"rodata-segment\", ${SHLIB_RODATA_ADDR})"
   fi
+  
   cat <<EOF
   ${RELOCATING+/* Adjust the address for the rodata segment.  We want to adjust up to
      the same address within the page on the next page up.  */
@@ -597,12 +630,11 @@ SEGMENT_START(\"rodata-segment\", ${SHLIB_RODATA_ADDR}) + SIZEOF_HEADERS"
   ${CREATE_SHLIB+. = ${SHLIB_RODATA_ADDR};}
   ${CREATE_PIE+. = ${SHLIB_RODATA_ADDR};}}
 EOF
-  if test -n "${SEPARATE_CODE}"; then
-    emit_early_ro
-    emit_dyn
-  fi
 fi
+}
 
+emit_rodata()
+{
 cat <<EOF
   ${WRITABLE_RODATA-${RODATA}}
   .${RODATA_NAME}1      ${RELOCATING-0} : { *(.${RODATA_NAME}1) }
@@ -621,7 +653,12 @@ cat <<EOF
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT+PROVIDE (__${ETEXT_NAME} = .);}}
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT+PROVIDE (_${ETEXT_NAME} = .);}}
   ${RELOCATING+${ETEXT_LAST_IN_RODATA_SEGMENT+PROVIDE (${ETEXT_NAME} = .);}}
+EOF
+}
 
+emit_data()
+{
+cat <<EOF
   ${RELOCATING+/* Adjust the address for the data segment.  We want to adjust up to
      the same address within the page on the next page up.  */}
   ${CREATE_SHLIB-${CREATE_PIE-${RELOCATING+. = ${DATA_ADDR-${DATA_SEGMENT_ALIGN}};}}}
@@ -712,7 +749,10 @@ cat <<EOF
   ${NOINIT}
   ${RELOCATING+. = ALIGN(${ALIGNMENT});}
 EOF
+}
 
+emit_large_data()
+{
 LARGE_DATA_ADDR=". = SEGMENT_START(\"ldata-segment\", ${LARGE_DATA_ADDR-.});"
 SHLIB_LARGE_DATA_ADDR=". = SEGMENT_START(\"ldata-segment\", ${SHLIB_LARGE_DATA_ADDR-.});"
 
@@ -730,9 +770,10 @@ cat <<EOF
   ${TINY_BSS_SECTION}
   ${STACK_ADDR+${STACK}}
 EOF
+}
 
-test -z "${NON_ALLOC_DYN}" || emit_dyn
-
+emit_misc()
+{
 source_sh $srcdir/scripttempl/misc-sections.sc
 source_sh $srcdir/scripttempl/DWARF.sc
 
@@ -741,5 +782,46 @@ cat <<EOF
   ${OTHER_SECTIONS}
   ${RELOCATING+${OTHER_SYMBOLS}}
   ${RELOCATING+${DISCARDED}}
+EOF
+}
+
+# ===========================================================================
+# The script:
+
+emit_header
+
+cat <<EOF
+SECTIONS
+{
+EOF
+
+  emit_executable_start
+
+  if test -z "${ALL_TEXT_BEFORE_RO}"; then
+    test -n "${SEPARATE_CODE}" || emit_early_ro
+    test -n "${NON_ALLOC_DYN}${SEPARATE_CODE}" || emit_dyn
+  fi
+  
+  align_text  
+  emit_text
+
+  align_rodata
+
+  if test -n "${ALL_TEXT_BEFORE_RO}"; then
+    test -n "${SEPARATE_CODE}" || emit_early_ro
+    test -n "${NON_ALLOC_DYN}${SEPARATE_CODE}" || emit_dyn
+  fi
+
+  test -z "${SEPARATE_CODE}" || emit_early_ro
+  test -z "${SEPARATE_CODE}" || emit_dyn
+  emit_rodata
+  
+  emit_data
+  emit_large_data
+
+  test -z "${NON_ALLOC_DYN}" || emit_dyn
+  emit_misc
+
+cat <<EOF
 }
 EOF