[binutils-gdb] Fixes the generation of dwarf line debug information for the msp430, even in the presence of functio

[Nick Clifton <nickc at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=0f8f0c57ea4742ad2d9b0598a18243331c1c06e3

commit 0f8f0c57ea4742ad2d9b0598a18243331c1c06e3
Author: Nick Clifton <nickc@redhat.com>
Date:   Mon Feb 23 14:53:02 2015 +0000

    Fixes the generation of dwarf line debug information for the msp430, even in the presence of function sections and linker garbage collection.
    
    	PR 17940
    	* dwarf2dbg.c (out_header): When generating dwarf sections use
    	real symbols not temps for the start and end symbols.
    	* config/tc-msp430.h (TC_FORCE_RELOCATION_SUB_SAME): Also prevent
    	adjustments to relocations in debug sections.
    	(TC_LINKRELAX_FIXUP): Likewise.
    
    	* elf32-msp430.c (msp430_elf_relax_delete_bytes): Adjust debug
    	symbols at end of sections.  Adjust function sizes.

Diff:
---
 bfd/ChangeLog          |  4 ++++
 bfd/elf32-msp430.c     | 49 +++++++++++++++++++++++++++++++++++++++++++++----
 gas/ChangeLog          |  9 +++++++++
 gas/config/tc-msp430.h |  5 +++--
 gas/dwarf2dbg.c        | 18 ++++++++++++++++--
 5 files changed, 77 insertions(+), 8 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index e9fb08b..f4391d7 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -3,6 +3,10 @@
 	PR 17914
 	* cpu-w65.c: Correct typos in license notice.
 
+	PR 17940
+	* elf32-msp430.c (msp430_elf_relax_delete_bytes): Adjust debug
+	symbols at end of sections.  Adjust function sizes.
+
 2015-02-20  Andreas Arnez  <arnez@linux.vnet.ibm.com>
 
 	* elf-bfd.h (elfcore_write_s390_vxrs_low): Add prototype.
diff --git a/bfd/elf32-msp430.c b/bfd/elf32-msp430.c
index c839ea0..fdab3d3 100644
--- a/bfd/elf32-msp430.c
+++ b/bfd/elf32-msp430.c
@@ -1656,9 +1656,38 @@ msp430_elf_relax_delete_bytes (bfd * abfd, asection * sec, bfd_vma addr,
   symtab_hdr = & elf_tdata (abfd)->symtab_hdr;
   isym = (Elf_Internal_Sym *) symtab_hdr->contents;
   for (isymend = isym + symtab_hdr->sh_info; isym < isymend; isym++)
-    if (isym->st_shndx == sec_shndx
-	&& isym->st_value > addr && isym->st_value < toaddr)
-      isym->st_value -= count;
+    {
+      const char * name;
+
+      name = bfd_elf_string_from_elf_section
+	(abfd, symtab_hdr->sh_link, isym->st_name);
+      name = (name == NULL || * name == 0) ? bfd_section_name (abfd, sec) : name;
+
+      if (isym->st_shndx != sec_shndx)
+	continue;
+      
+      if (isym->st_value > addr
+	  && (isym->st_value < toaddr
+	      /* We also adjust a symbol at the end of the section if its name is
+		 on the list below.  These symbols are used for debug info
+		 generation and they refer to the end of the current section, not
+		 the start of the next section.  */
+	      || (isym->st_value == toaddr
+		  && name != NULL
+		  && (CONST_STRNEQ (name, ".Letext")
+		      || CONST_STRNEQ (name, ".LFE")))))
+	{
+	  if (isym->st_value < addr + count)
+	    isym->st_value = addr;
+	  else
+	    isym->st_value -= count;
+	}
+      /* Adjust the function symbol's size as well.  */
+      else if (ELF_ST_TYPE (isym->st_info) == STT_FUNC
+	       && isym->st_value + isym->st_size > addr
+	       && isym->st_value + isym->st_size < toaddr)
+	isym->st_size -= count;
+    }
 
   /* Now adjust the global symbols defined in this section.  */
   symcount = (symtab_hdr->sh_size / sizeof (Elf32_External_Sym)
@@ -1674,7 +1703,19 @@ msp430_elf_relax_delete_bytes (bfd * abfd, asection * sec, bfd_vma addr,
 	  && sym_hash->root.u.def.section == sec
 	  && sym_hash->root.u.def.value > addr
 	  && sym_hash->root.u.def.value < toaddr)
-	sym_hash->root.u.def.value -= count;
+	{
+	  if (sym_hash->root.u.def.value < addr + count)
+	    sym_hash->root.u.def.value = addr;
+	  else
+	    sym_hash->root.u.def.value -= count;
+	}
+      /* Adjust the function symbol's size as well.  */
+      else if (sym_hash->root.type == bfd_link_hash_defined
+	       && sym_hash->root.u.def.section == sec
+	       && sym_hash->type == STT_FUNC
+	       && sym_hash->root.u.def.value + sym_hash->size > addr
+	       && sym_hash->root.u.def.value + sym_hash->size < toaddr)
+	sym_hash->size -= count;
     }
 
   return TRUE;
diff --git a/gas/ChangeLog b/gas/ChangeLog
index fe711bf..93dd2dd 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,12 @@
+2015-02-23  Nick Clifton  <nickc@redhat.com>
+
+	PR 17940
+	* dwarf2dbg.c (out_header): When generating dwarf sections use
+	real symbols not temps for the start and end symbols.
+	* config/tc-msp430.h (TC_FORCE_RELOCATION_SUB_SAME): Also prevent
+	adjustments to relocations in debug sections.
+	(TC_LINKRELAX_FIXUP): Likewise.
+
 2015-02-19  Alan Modra  <amodra@gmail.com>
 
 	* doc/as.texinfo (Local Symbol Names): Don't use ':' in pxref.
diff --git a/gas/config/tc-msp430.h b/gas/config/tc-msp430.h
index 657dc1a..08115ac 100644
--- a/gas/config/tc-msp430.h
+++ b/gas/config/tc-msp430.h
@@ -159,7 +159,8 @@ extern bfd_boolean msp430_allow_local_subtract (expressionS *, expressionS *, se
    linker, but this fix is simpler, and it pretty much only affects
    object size a little bit.  */
 #define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEC)	\
-  (((SEC)->flags & SEC_CODE) != 0		\
+  (   ((SEC)->flags & SEC_CODE) != 0		\
+   || ((SEC)->flags & SEC_DEBUGGING) != 0	\
    || ! SEG_NORMAL (SEC)			\
    || TC_FORCE_RELOCATION (FIX))
 
@@ -169,4 +170,4 @@ extern bfd_boolean msp430_allow_local_subtract (expressionS *, expressionS *, se
 
 #define DWARF2_USE_FIXED_ADVANCE_PC 1
 
-#define TC_LINKRELAX_FIXUP(seg) (seg->flags & SEC_CODE)
+#define TC_LINKRELAX_FIXUP(seg) ((seg->flags & SEC_CODE) || (seg->flags & SEC_DEBUGGING))
diff --git a/gas/dwarf2dbg.c b/gas/dwarf2dbg.c
index 5dfd980..9177bdf 100644
--- a/gas/dwarf2dbg.c
+++ b/gas/dwarf2dbg.c
@@ -1467,8 +1467,22 @@ out_header (asection *sec, expressionS *exp)
   symbolS *end_sym;
 
   subseg_set (sec, 0);
-  start_sym = symbol_temp_new_now ();
-  end_sym = symbol_temp_make ();
+#if 1
+  if (flag_dwarf_sections)
+    {
+      /* If we are going to put the start and end symbols in different
+	 sections, then we need real symbols, not just fake, local ones.  */
+      frag_now_fix ();
+      start_sym = symbol_make (".Ldebug_line_start");
+      end_sym = symbol_make (".Ldebug_line_end");
+      symbol_set_value_now (start_sym);
+    }
+  else
+#endif
+    {
+      start_sym = symbol_temp_new_now ();
+      end_sym = symbol_temp_make ();
+    }
 
   /* Total length of the information.  */
   exp->X_op = O_subtract;