Define DIFF_EXPR_OK for avr target to allow PC relative difference relocation.

When generating relocation (tc_gen_reloc) 32 bit relocation fixup
is changed to new 32 bit PC relative relocation if the fixup has pc-relative
flag set.

bfd/ChangeLog

2015-07-06  Pitchumani Sivanupandi <pitchumani.s@atmel.com>

    * elf32-avr.c: Add 32 bit PC relative relocation for AVR target.

gas/ChangeLog

2015-07-06  Pitchumani Sivanupandi <pitchumani.s@atmel.com>

    * config/tc-avr.c (tc_gen_reloc): Change 32 bit relocation to
    32 bit PC relative and update offset if the fixup is pc-relative.
    * config/tc-avr.h (DIFF_EXPR_OK): Define to enable PC relative diff
    relocs.

gas/testsuite/ChangeLog

2015-07-06  Pitchumani Sivanupandi <pitchumani.s@atmel.com>

    * gas/avr/pc-relative-reloc.d: New test for 32 bit pc relative reloc.
    * gas/avr/per-function-debugline.s: New test source.

include/ChangeLog

2015-07-06  Pitchumani Sivanupandi <pitchumani.s@atmel.com>

    * elf/avr.h: Add new 32 bit PC relative relocation.

ld/testsuite/ChangeLog

2015-07-06  Pitchumani Sivanupandi <pitchumani.s@atmel.com>

    * ld-avr/gc-section-debugline.d: New test.
    * ld-avr/per-function-debugline.s: Source for new test.

13 files changed, 270 insertions, 4 deletions

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 97d3ea3..e6d1783 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,7 @@
+2015-07-08  Pitchumani Sivanupandi <pitchumani.s@atmel.com>
+
+	* elf32-avr.c: Add 32 bit PC relative relocation for AVR target.
+
 2015-07-05  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* elf64-ppc.c (toc_adjusting_stub_needed): Use the symbol value
diff --git a/bfd/elf32-avr.c b/bfd/elf32-avr.c
index 8651f49..bd57ab7 100644
--- a/bfd/elf32-avr.c
+++ b/bfd/elf32-avr.c
@@ -641,7 +641,22 @@ static reloc_howto_type elf_avr_howto_table[] =
 	 FALSE,			/* partial_inplace */
 	 0xffffff,		/* src_mask */
 	 0xffffff,		/* dst_mask */
-	 FALSE) 		/* pcrel_offset */
+	 FALSE), 		/* pcrel_offset */
+
+  /* A 32 bit PC relative relocation.  */
+  HOWTO (R_AVR_32_PCREL,	/* type */
+	 0,				/* rightshift */
+	 2,				/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 TRUE,			/* pc_relative */
+	 0,				/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 bfd_elf_generic_reloc, /* special_function */
+	 "R_AVR_32_PCREL",	/* name */
+	 FALSE,			/* partial_inplace */
+	 0xffffffff,	/* src_mask */
+	 0xffffffff,	/* dst_mask */
+	 TRUE),			/* pcrel_offset */
 };
 
 /* Map BFD reloc types to AVR ELF reloc types.  */
@@ -689,7 +704,8 @@ static const struct avr_reloc_map avr_reloc_map[] =
   { BFD_RELOC_AVR_DIFF32,           R_AVR_DIFF32 },
   { BFD_RELOC_AVR_LDS_STS_16,       R_AVR_LDS_STS_16},
   { BFD_RELOC_AVR_PORT6,            R_AVR_PORT6},
-  { BFD_RELOC_AVR_PORT5,            R_AVR_PORT5}
+  { BFD_RELOC_AVR_PORT5,            R_AVR_PORT5},
+  { BFD_RELOC_32_PCREL,             R_AVR_32_PCREL}
 };
 
 /* Meant to be filled one day with the wrap around address for the
diff --git a/gas/ChangeLog b/gas/ChangeLog
index f9d4892..4439de5 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,10 @@
+2015-07-08  Pitchumani Sivanupandi <pitchumani.s@atmel.com>
+
+	* config/tc-avr.c (tc_gen_reloc): Change 32 bit relocation to
+	32 bit PC relative and update offset if the fixup is pc-relative.
+	* config/tc-avr.h (DIFF_EXPR_OK): Define to enable PC relative diff
+	relocs.
+
 2015-07-03  Alan Modra  <amodra@gmail.com>
 
 	* config/tc-ppc.c (md_show_usage): Add -m821, -m850, -m860.
diff --git a/gas/config/tc-avr.c b/gas/config/tc-avr.c
index 5c8982c..c69a91c 100644
--- a/gas/config/tc-avr.c
+++ b/gas/config/tc-avr.c
@@ -1618,6 +1618,7 @@ tc_gen_reloc (asection *seg ATTRIBUTE_UNUSED,
 	      fixS *fixp)
 {
   arelent *reloc;
+  bfd_reloc_code_real_type code = fixp->fx_r_type;
 
   if (fixp->fx_subsy != NULL)
     {
@@ -1631,7 +1632,21 @@ tc_gen_reloc (asection *seg ATTRIBUTE_UNUSED,
   *reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
 
   reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
-  reloc->howto = bfd_reloc_type_lookup (stdoutput, fixp->fx_r_type);
+
+  if ((fixp->fx_r_type == BFD_RELOC_32) && (fixp->fx_pcrel))
+    {
+      if (seg->use_rela_p)
+        fixp->fx_offset -= md_pcrel_from_section (fixp, seg);
+      else
+        fixp->fx_offset = reloc->address;
+
+      code = BFD_RELOC_32_PCREL;
+    }
+
+  reloc->addend = fixp->fx_offset;
+
+  reloc->howto = bfd_reloc_type_lookup (stdoutput, code);
+
   if (reloc->howto == (reloc_howto_type *) NULL)
     {
       as_bad_where (fixp->fx_file, fixp->fx_line,
@@ -1644,7 +1659,6 @@ tc_gen_reloc (asection *seg ATTRIBUTE_UNUSED,
       || fixp->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
     reloc->address = fixp->fx_offset;
 
-  reloc->addend = fixp->fx_offset;
 
   return reloc;
 }
diff --git a/gas/config/tc-avr.h b/gas/config/tc-avr.h
index 21471c8..5501ef0 100644
--- a/gas/config/tc-avr.h
+++ b/gas/config/tc-avr.h
@@ -45,6 +45,8 @@
    nonstandard escape sequences in a string.  */
 #define ONLY_STANDARD_ESCAPES
 
+#define DIFF_EXPR_OK    /* .-foo gets turned into PC relative relocs */
+
 /* GAS will call this function for any expression that can not be
    recognized.  When the function is called, `input_line_pointer'
    will point to the start of the expression.  */
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index a045c85..aecbef6 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-08  Pitchumani Sivanupandi <pitchumani.s@atmel.com>
+
+	* gas/avr/pc-relative-reloc.d: New test for 32 bit pc relative reloc.
+	* gas/avr/per-function-debugline.s: New test source.
+
 2015-07-03  Alan Modra  <alan@squeak.grove.modra.org>
 
 	* gas/ppc/titan.d: Correct mfmcsrr0 disassembly.
diff --git a/gas/testsuite/gas/avr/pc-relative-reloc.d b/gas/testsuite/gas/avr/pc-relative-reloc.d
new file mode 100644
index 0000000..cc22b0b
--- /dev/null
+++ b/gas/testsuite/gas/avr/pc-relative-reloc.d
@@ -0,0 +1,19 @@
+#name: 32 bit PC relative reloc
+#as: -mmcu=avr51 -gdwarf-sections -g
+#objdump: -r
+#source: per-function-debugline.s
+#target: avr-*-*
+
+.*:     file format elf32-avr
+
+RELOCATION RECORDS FOR \[.text.main\]:
+#...
+
+
+RELOCATION RECORDS FOR \[.debug_line\]:
+OFFSET   TYPE              VALUE 
+00000000 R_AVR_32_PCREL    .debug_line_end-0x00000004
+
+
+RELOCATION RECORDS FOR \[.debug_line.text.main\]:
+#...
diff --git a/gas/testsuite/gas/avr/per-function-debugline.s b/gas/testsuite/gas/avr/per-function-debugline.s
new file mode 100644
index 0000000..4db56e5
--- /dev/null
+++ b/gas/testsuite/gas/avr/per-function-debugline.s
@@ -0,0 +1,35 @@
+	.file	"per-function-debugline.s"
+__SP_H__ = 0x3e
+__SP_L__ = 0x3d
+__SREG__ = 0x3f
+__RAMPZ__ = 0x3b
+__tmp_reg__ = 0
+__zero_reg__ = 1
+	.comm	g,2,1
+	.section	.text.main,"ax",@progbits
+.global	main
+	.type	main, @function
+main:
+	push r28
+	push r29
+	in r28,__SP_L__
+	in r29,__SP_H__
+/* prologue: function */
+/* frame size = 0 */
+/* stack size = 2 */
+.L__stack_usage = 2
+	call foo
+	lds r24,g
+	lds r25,g+1
+	sbiw r24,1
+	sts g+1,r25
+	sts g,r24
+	lds r24,g
+	lds r25,g+1
+/* epilogue start */
+	pop r29
+	pop r28
+	ret
+	.size	main, .-main
+	.ident	"GCC: (GNU) 6.0.0 20150630 (experimental)"
+.global __do_clear_bss
diff --git a/include/ChangeLog b/include/ChangeLog
index d85a1b0..015e304 100644
--- a/include/ChangeLog
+++ b/include/ChangeLog
@@ -1,3 +1,7 @@
+2015-07-08  Pitchumani Sivanupandi <pitchumani.s@atmel.com>
+
+	* elf/avr.h: Add new 32 bit PC relative relocation.
+
 2015-06-26  Matthew Fortune  <matthew.fortune@imgtec.com>
 
 	* elf/mips.h (DT_MIPS_RLD_MAP_REL): New macro.
diff --git a/include/elf/avr.h b/include/elf/avr.h
index 115296d..f0ef479 100644
--- a/include/elf/avr.h
+++ b/include/elf/avr.h
@@ -87,6 +87,7 @@ START_RELOC_NUMBERS (elf_avr_reloc_type)
      RELOC_NUMBER (R_AVR_LDS_STS_16,           33)
      RELOC_NUMBER (R_AVR_PORT6,                34)
      RELOC_NUMBER (R_AVR_PORT5,                35)
+     RELOC_NUMBER (R_AVR_32_PCREL,             36)
 END_RELOC_NUMBERS (R_AVR_max)
 
 #endif /* _ELF_AVR_H */
diff --git a/ld/testsuite/ChangeLog b/ld/testsuite/ChangeLog
index 1ee6aa1..9bf1e5b 100644
--- a/ld/testsuite/ChangeLog
+++ b/ld/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2015-07-08  Pitchumani Sivanupandi <pitchumani.s@atmel.com>
+
+	* ld-avr/gc-section-debugline.d: New test.
+	* ld-avr/per-function-debugline.s: Source for new test.
+
 2015-07-05  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* ld-powerpc/tocopt6-inc.s, ld-powerpc/tocopt6a.s,
diff --git a/ld/testsuite/ld-avr/gc-section-debugline.d b/ld/testsuite/ld-avr/gc-section-debugline.d
new file mode 100644
index 0000000..e98ff6c
--- /dev/null
+++ b/ld/testsuite/ld-avr/gc-section-debugline.d
@@ -0,0 +1,70 @@
+#name: dwarf decoded line after gc-sections
+#as: -mmcu=avr51 -gdwarf-sections -g
+#ld: -mavr51 -gc-sections -u main
+#objdump: --dwarf=decodedline
+#source: per-function-debugline.s
+#target: avr-*-*
+
+.*:     file format elf32-avr
+
+Decoded dump of debug contents of section .debug_line:
+
+CU: .*:
+File name                            Line number    Starting address
+per-function-debugline.s                      39                   0
+
+per-function-debugline.s                      40                 0x2
+
+per-function-debugline.s                      41                 0x4
+
+per-function-debugline.s                      42                 0x6
+
+per-function-debugline.s                      47                 0x8
+
+per-function-debugline.s                      48                 0xc
+
+per-function-debugline.s                      49                0x10
+
+per-function-debugline.s                      50                0x12
+
+per-function-debugline.s                      51                0x16
+
+per-function-debugline.s                      52                0x1a
+
+per-function-debugline.s                      54                0x1c
+
+per-function-debugline.s                      55                0x1e
+
+per-function-debugline.s                      56                0x20
+
+per-function-debugline.s                      62                0x22
+
+per-function-debugline.s                      63                0x24
+
+per-function-debugline.s                      64                0x26
+
+per-function-debugline.s                      65                0x28
+
+per-function-debugline.s                      70                0x2a
+
+per-function-debugline.s                      71                0x2e
+
+per-function-debugline.s                      72                0x32
+
+per-function-debugline.s                      73                0x36
+
+per-function-debugline.s                      74                0x38
+
+per-function-debugline.s                      75                0x3c
+
+per-function-debugline.s                      76                0x40
+
+per-function-debugline.s                      77                0x44
+
+per-function-debugline.s                      79                0x48
+
+per-function-debugline.s                      80                0x4a
+
+per-function-debugline.s                      81                0x4c
+
+
diff --git a/ld/testsuite/ld-avr/per-function-debugline.s b/ld/testsuite/ld-avr/per-function-debugline.s
new file mode 100644
index 0000000..361cb00
--- /dev/null
+++ b/ld/testsuite/ld-avr/per-function-debugline.s
@@ -0,0 +1,84 @@
+	.file	"per-function-debugline.s"
+__SP_H__ = 0x3e
+__SP_L__ = 0x3d
+__SREG__ = 0x3f
+__RAMPZ__ = 0x3b
+__tmp_reg__ = 0
+__zero_reg__ = 1
+	.comm	g,2,1
+	.section	.text.bar,"ax",@progbits
+.global	bar
+	.type	bar, @function
+bar:
+	push r28
+	push r29
+	rcall .
+	in r28,__SP_L__
+	in r29,__SP_H__
+/* prologue: function */
+/* frame size = 2 */
+/* stack size = 4 */
+.L__stack_usage = 4
+	ldd r24,Y+1
+	ldd r25,Y+2
+	adiw r24,1
+	std Y+2,r25
+	std Y+1,r24
+	nop
+/* epilogue start */
+	pop __tmp_reg__
+	pop __tmp_reg__
+	pop r29
+	pop r28
+	ret
+	.size	bar, .-bar
+	.section	.text.foo,"ax",@progbits
+.global	foo
+	.type	foo, @function
+foo:
+	push r28
+	push r29
+	in r28,__SP_L__
+	in r29,__SP_H__
+/* prologue: function */
+/* frame size = 0 */
+/* stack size = 2 */
+.L__stack_usage = 2
+	lds r24,g
+	lds r25,g+1
+	adiw r24,1
+	sts g+1,r25
+	sts g,r24
+	nop
+/* epilogue start */
+	pop r29
+	pop r28
+	ret
+	.size	foo, .-foo
+	.section	.text.main,"ax",@progbits
+.global	main
+	.type	main, @function
+main:
+	push r28
+	push r29
+	in r28,__SP_L__
+	in r29,__SP_H__
+/* prologue: function */
+/* frame size = 0 */
+/* stack size = 2 */
+.L__stack_usage = 2
+	call foo
+	lds r24,g
+	lds r25,g+1
+	sbiw r24,1
+	sts g+1,r25
+	sts g,r24
+	lds r24,g
+	lds r25,g+1
+/* epilogue start */
+	pop r29
+	pop r28
+	ret
+	.size	main, .-main
+	.ident	"GCC: (GNU) 6.0.0 20150630 (experimental)"
+.global __do_clear_bss