meta-xilinx/meta-xilinx-bsp/recipes-microblaze/gdb/files/0014-LOCAL-Fixup-debug_loc-sections-after-linker-relaxati.patch

From aca2758cff1f8fdc5ad7b6076ef985ba9ec5f857 Mon Sep 17 00:00:00 2001
From: David Holsgrove <david.holsgrove@xilinx.com>
Date: Mon, 4 Feb 2013 12:15:22 +1000
Subject: [PATCH 14/16] [LOCAL]: Fixup debug_loc sections after linker
 relaxation

Adds a new reloctype R_MICROBLAZE_32_NONE, used for passing
reloc info from the assembler to the linker when the linker
manages to fully resolve a local symbol reference.

This is a workaround for design flaws in the assembler to
linker interface with regards to linker relaxation.

Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: David Holsgrove <david.holsgrove@xilinx.com>
Upstream-Status: Pending
---
 bfd/bfd-in2.h              |  5 +++++
 bfd/elf32-microblaze.c     | 45 +++++++++++++++++++++++++++++++++++++--------
 bfd/libbfd.h               |  1 +
 bfd/reloc.c                |  6 ++++++
 include/elf/microblaze.h   |  1 +
 5 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h
index 8b7f2ee..de38907 100644
--- a/bfd/bfd-in2.h
+++ b/bfd/bfd-in2.h
@@ -5449,6 +5449,11 @@ value relative to the read-write small data area anchor  */
 expressions of the form "Symbol Op Symbol"  */
   BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM,
 
+/* This is a 32 bit reloc that stores the 32 bit pc relative
+value in two words (with an imm instruction).  No relocation is 
+done here - only used for relaxing  */
+  BFD_RELOC_MICROBLAZE_32_NONE,
+
 /* This is a 64 bit reloc that stores the 32 bit pc relative
 value in two words (with an imm instruction).  No relocation is
 done here - only used for relaxing  */
diff --git a/bfd/elf32-microblaze.c b/bfd/elf32-microblaze.c
index f90df47..a3f89b9 100644
--- a/bfd/elf32-microblaze.c
+++ b/bfd/elf32-microblaze.c
@@ -177,6 +177,20 @@ static reloc_howto_type microblaze_elf_howto_raw[] =
           FALSE), 		/* PC relative offset?  */
 
    /* This reloc does nothing.  Used for relaxation.  */
+   HOWTO (R_MICROBLAZE_32_NONE,	/* Type.  */
+          0,			/* Rightshift.  */
+          2,			/* Size (0 = byte, 1 = short, 2 = long).  */
+          32,			/* Bitsize.  */
+          TRUE,			/* PC_relative.  */
+          0,			/* Bitpos.  */
+          complain_overflow_bitfield,  /* Complain on overflow.  */
+          NULL,                  /* Special Function.  */
+          "R_MICROBLAZE_32_NONE",/* Name.  */
+          FALSE,		/* Partial Inplace.  */
+          0,			/* Source Mask.  */
+          0,			/* Dest Mask.  */
+          FALSE),		/* PC relative offset?  */
+
    HOWTO (R_MICROBLAZE_64_NONE,	/* Type.  */
           0,			/* Rightshift.  */
           2,			/* Size (0 = byte, 1 = short, 2 = long).  */
@@ -532,7 +546,10 @@ microblaze_elf_reloc_type_lookup (bfd * abfd ATTRIBUTE_UNUSED,
     case BFD_RELOC_NONE:
       microblaze_reloc = R_MICROBLAZE_NONE;
       break;
-    case BFD_RELOC_MICROBLAZE_64_NONE:
+    case BFD_RELOC_MICROBLAZE_32_NONE:
+      microblaze_reloc = R_MICROBLAZE_32_NONE;
+      break;
+     case BFD_RELOC_MICROBLAZE_64_NONE:
       microblaze_reloc = R_MICROBLAZE_64_NONE;
       break;
     case BFD_RELOC_32:
@@ -1913,14 +1930,22 @@ microblaze_elf_relax_section (bfd *abfd,
 	        }
 	      break;
 	    case R_MICROBLAZE_NONE:
+	    case R_MICROBLAZE_32_NONE:
 	      {
 	        /* This was a PC-relative instruction that was
  		   completely resolved.  */
 	        int sfix, efix;
+		unsigned int val;
 	        bfd_vma target_address;
 	        target_address = irel->r_addend + irel->r_offset;
 	        sfix = calc_fixup (irel->r_offset, 0, sec);
 	        efix = calc_fixup (target_address, 0, sec);
+
+                /* Validate the in-band val.  */
+                val = bfd_get_32 (abfd, contents + irel->r_offset);
+                if (val != irel->r_addend && ELF32_R_TYPE (irel->r_info) == R_MICROBLAZE_32_NONE) {
+                    fprintf(stderr, "%d: CORRUPT relax reloc %x %lx\n", __LINE__, val, irel->r_addend);
+                }
 	        irel->r_addend -= (efix - sfix);
 	        /* Should use HOWTO.  */
 	        microblaze_bfd_write_imm_value_32 (abfd, contents + irel->r_offset,
@@ -1968,12 +1993,16 @@ microblaze_elf_relax_section (bfd *abfd,
           irelscanend = irelocs + o->reloc_count;
           for (irelscan = irelocs; irelscan < irelscanend; irelscan++)
             {
-              if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_NONE)
+              if (1 && ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_32_NONE)
                 {
                   unsigned int val;
 
                   isym = isymbuf + ELF32_R_SYM (irelscan->r_info);
 
+                  /* hax: We only do the following fixup for debug location lists.  */
+                  if (strcmp(".debug_loc", o->name))
+                    continue;
+
                   /* This was a PC-relative instruction that was completely resolved.  */
                   if (ocontents == NULL)
                     {
@@ -1998,15 +2027,15 @@ microblaze_elf_relax_section (bfd *abfd,
 		        }
 		    }
 
-                  irelscan->r_addend -= calc_fixup (irelscan->r_addend
-                                                    + isym->st_value, sec);
                   val = bfd_get_32 (abfd, ocontents + irelscan->r_offset);
+                  if (val != irelscan->r_addend) {
+			fprintf(stderr, "%d: CORRUPT relax reloc! %x %lx\n", __LINE__, val, irelscan->r_addend);
+                  }
+
+                  irelscan->r_addend -= calc_fixup (irelscan->r_addend, 0, sec);
                   microblaze_bfd_write_imm_value_32 (abfd, ocontents + irelscan->r_offset,
                                                      irelscan->r_addend);
               }
-              if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_64_NONE) {
-                  fprintf(stderr, "Unhandled NONE 64\n");
-              }
               if (ELF32_R_TYPE (irelscan->r_info) == (int) R_MICROBLAZE_32)
                 {
 	          isym = isymbuf + ELF32_R_SYM (irelscan->r_info);
@@ -2066,7 +2095,7 @@ microblaze_elf_relax_section (bfd *abfd,
 			      elf_section_data (o)->this_hdr.contents = ocontents;
 			    }
 			}
-		      irelscan->r_addend -= calc_fixup (irel->r_addend
+		      irelscan->r_addend -= calc_fixup (irelscan->r_addend
 							+ isym->st_value,
 							0,
 							sec);
diff --git a/bfd/libbfd.h b/bfd/libbfd.h
index 09f307f..840c662 100644
--- a/bfd/libbfd.h
+++ b/bfd/libbfd.h
@@ -2644,6 +2644,7 @@ static const char *const bfd_reloc_code_real_names[] = { "@@uninitialized@@",
   "BFD_RELOC_MICROBLAZE_32_ROSDA",
   "BFD_RELOC_MICROBLAZE_32_RWSDA",
   "BFD_RELOC_MICROBLAZE_32_SYM_OP_SYM",
+  "BFD_RELOC_MICROBLAZE_32_NONE",
   "BFD_RELOC_MICROBLAZE_64_NONE",
   "BFD_RELOC_MICROBLAZE_64_GOTPC",
   "BFD_RELOC_MICROBLAZE_64_GOT",
diff --git a/bfd/reloc.c b/bfd/reloc.c
index 7f46c58..5bcd52d 100644
--- a/bfd/reloc.c
+++ b/bfd/reloc.c
@@ -6396,6 +6396,12 @@ ENUMDOC
   This is a 32 bit reloc for the microblaze to handle
   expressions of the form "Symbol Op Symbol"
 ENUM
+  BFD_RELOC_MICROBLAZE_32_NONE
+ENUMDOC
+  This is a 32 bit reloc that stores the 32 bit pc relative
+  value in two words (with an imm instruction).  No relocation is
+  done here - only used for relaxing
+ENUM
   BFD_RELOC_MICROBLAZE_64_NONE
 ENUMDOC
   This is a 64 bit reloc that stores the 32 bit pc relative
diff --git a/include/elf/microblaze.h b/include/elf/microblaze.h
index effca20..f8420dc 100644
--- a/include/elf/microblaze.h
+++ b/include/elf/microblaze.h
@@ -58,6 +58,7 @@ START_RELOC_NUMBERS (elf_microblaze_reloc_type)
   RELOC_NUMBER (R_MICROBLAZE_TLSDTPREL64, 27)   /* TLS Offset Within TLS Block */
   RELOC_NUMBER (R_MICROBLAZE_TLSGOTTPREL32, 28) /* TLS Offset From Thread Pointer */
   RELOC_NUMBER (R_MICROBLAZE_TLSTPREL32, 29)    /* TLS Offset From Thread Pointer */
+  RELOC_NUMBER (R_MICROBLAZE_32_NONE, 30)
    
 END_RELOC_NUMBERS (R_MICROBLAZE_max)
 
-- 
1.9.0