gas/

	* config/tc-arm.c (parse_address_main): Handle -0 offsets.
	(encode_arm_addr_mode_2): Set default sign of zero here ...
	(encode_arm_addr_mode_3): ... and here.
	(encode_arm_cp_address): ... and here.
	(md_apply_fix): Use default sign of zero here.

	gas/testsuite/
	* gas/arm/inst.d: Adjust for signed zero offsets.
	* gas/arm/ldst-offset0.d: New test.
	* gas/arm/ldst-offset0.s: New test.
	* gas/arm/offset-1.d: New test.
	* gas/arm/offset-1.s: New test.

	ld/testsuite/
	Adjust tests for zero offset formatting.
	* ld-arm/cortex-a8-fix-bcc-plt.d: Adjust.
	* ld-arm/farcall-arm-arm-pic-veneer.d: Adjust.
	* ld-arm/farcall-arm-thumb.d: Adjust.
	* ld-arm/farcall-group-size2.d: Adjust.
	* ld-arm/farcall-group.d: Adjust.
	* ld-arm/farcall-mix.d: Adjust.
	* ld-arm/farcall-mix2.d: Adjust.
	* ld-arm/farcall-mixed-lib-v4t.d: Adjust.
	* ld-arm/farcall-mixed-lib.d: Adjust.
	* ld-arm/farcall-thumb-arm-blx-pic-veneer.d: Adjust.
	* ld-arm/farcall-thumb-arm-pic-veneer.d: Adjust.
	* ld-arm/farcall-thumb-thumb.d: Adjust.
	* ld-arm/ifunc-10.dd: Adjust.
	* ld-arm/ifunc-3.dd: Adjust.
	* ld-arm/ifunc-4.dd: Adjust.
	* ld-arm/ifunc-5.dd: Adjust.
	* ld-arm/ifunc-6.dd: Adjust.
	* ld-arm/ifunc-7.dd: Adjust.
	* ld-arm/ifunc-8.dd: Adjust.
	* ld-arm/jump-reloc-veneers-long.d: Adjust.
	* ld-arm/tls-longplt-lib.d: Adjust.
	* ld-arm/tls-thumb1.d: Adjust.

	opcodes/
	* arm-dis.c (print_insn_coprocessor): Explicitly print #-0
	as address offset.
	(print_arm_address): Likewise. Elide positive #0 appropriately.
	(print_insn_arm): Likewise.

8 files changed, 249 insertions, 15 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 6e40507..8d4019b 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,12 @@
+2011-06-02  Jie Zhang jie@codesourcery.com
+	    Nathan Sidwell nathan@codesourcery.com
+
+	* config/tc-arm.c (parse_address_main): Handle -0 offsets.
+	(encode_arm_addr_mode_2): Set default sign of zero here ...
+	(encode_arm_addr_mode_3): ... and here.
+	(encode_arm_cp_address): ... and here.
+	(md_apply_fix): Use default sign of zero here.
+
 2011-06-02  Nick Clifton  <nickc@redhat.com>
 
 	* as.c: Fix spelling typo.
diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c
index 415663d..c17a1dc 100644
--- a/gas/config/tc-arm.c
+++ b/gas/config/tc-arm.c
@@ -5200,8 +5200,24 @@ parse_address_main (char **str, int i, int group_relocations,
 		}
             }
           else
-	    if (my_get_expression (&inst.reloc.exp, &p, GE_IMM_PREFIX))
-	      return PARSE_OPERAND_FAIL;
+	    {
+	      char *q = p;
+	      if (my_get_expression (&inst.reloc.exp, &p, GE_IMM_PREFIX))
+		return PARSE_OPERAND_FAIL;
+	      /* If the offset is 0, find out if it's a +0 or -0.  */
+	      if (inst.reloc.exp.X_op == O_constant
+		  && inst.reloc.exp.X_add_number == 0)
+		{
+		  skip_whitespace (q);
+		  if (*q == '#')
+		    {
+		      q++;
+		      skip_whitespace (q);
+		    }
+		  if (*q == '-')
+		    inst.operands[i].negative = 1;
+		}
+	    }
 	}
     }
   else if (skip_past_char (&p, ':') == SUCCESS)
@@ -5275,6 +5291,7 @@ parse_address_main (char **str, int i, int group_relocations,
 	    }
 	  else
 	    {
+	      char *q = p;
 	      if (inst.operands[i].negative)
 		{
 		  inst.operands[i].negative = 0;
@@ -5282,6 +5299,19 @@ parse_address_main (char **str, int i, int group_relocations,
 		}
 	      if (my_get_expression (&inst.reloc.exp, &p, GE_IMM_PREFIX))
 		return PARSE_OPERAND_FAIL;
+	      /* If the offset is 0, find out if it's a +0 or -0.  */
+	      if (inst.reloc.exp.X_op == O_constant
+		  && inst.reloc.exp.X_add_number == 0)
+		{
+		  skip_whitespace (q);
+		  if (*q == '#')
+		    {
+		      q++;
+		      skip_whitespace (q);
+		    }
+		  if (*q == '-')
+		    inst.operands[i].negative = 1;
+		}
 	    }
 	}
     }
@@ -7038,7 +7068,12 @@ encode_arm_addr_mode_2 (int i, bfd_boolean is_t)
 	}
 
       if (inst.reloc.type == BFD_RELOC_UNUSED)
-	inst.reloc.type = BFD_RELOC_ARM_OFFSET_IMM;
+	{
+	  /* Prefer + for zero encoded value.  */
+	  if (!inst.operands[i].negative)
+	    inst.instruction |= INDEX_UP;
+	  inst.reloc.type = BFD_RELOC_ARM_OFFSET_IMM;
+	}
     }
 }
 
@@ -7074,7 +7109,13 @@ encode_arm_addr_mode_3 (int i, bfd_boolean is_t)
 		  BAD_PC_WRITEBACK);
       inst.instruction |= HWOFFSET_IMM;
       if (inst.reloc.type == BFD_RELOC_UNUSED)
-	inst.reloc.type = BFD_RELOC_ARM_OFFSET_IMM8;
+	{
+	  /* Prefer + for zero encoded value.  */
+	  if (!inst.operands[i].negative)
+	    inst.instruction |= INDEX_UP;
+
+	  inst.reloc.type = BFD_RELOC_ARM_OFFSET_IMM8;
+	}
     }
 }
 
@@ -7136,6 +7177,10 @@ encode_arm_cp_address (int i, int wb_ok, int unind_ok, int reloc_override)
         inst.reloc.type = BFD_RELOC_ARM_CP_OFF_IMM;
     }
 
+  /* Prefer + for zero encoded value.  */
+  if (!inst.operands[i].negative)
+    inst.instruction |= INDEX_UP;
+
   return SUCCESS;
 }
 
@@ -20447,7 +20492,7 @@ md_apply_fix (fixS *	fixP,
 	value = 0;
 
     case BFD_RELOC_ARM_LITERAL:
-      sign = value >= 0;
+      sign = value > 0;
 
       if (value < 0)
 	value = - value;
@@ -20465,14 +20510,19 @@ md_apply_fix (fixS *	fixP,
 	}
 
       newval = md_chars_to_number (buf, INSN_SIZE);
-      newval &= 0xff7ff000;
-      newval |= value | (sign ? INDEX_UP : 0);
+      if (value == 0)
+	newval &= 0xfffff000;
+      else
+	{
+	  newval &= 0xff7ff000;
+	  newval |= value | (sign ? INDEX_UP : 0);
+	}
       md_number_to_chars (buf, newval, INSN_SIZE);
       break;
 
     case BFD_RELOC_ARM_OFFSET_IMM8:
     case BFD_RELOC_ARM_HWLITERAL:
-      sign = value >= 0;
+      sign = value > 0;
 
       if (value < 0)
 	value = - value;
@@ -20489,8 +20539,13 @@ md_apply_fix (fixS *	fixP,
 	}
 
       newval = md_chars_to_number (buf, INSN_SIZE);
-      newval &= 0xff7ff0f0;
-      newval |= ((value >> 4) << 8) | (value & 0xf) | (sign ? INDEX_UP : 0);
+      if (value == 0)
+	newval &= 0xfffff0f0;
+      else
+	{
+	  newval &= 0xff7ff0f0;
+	  newval |= ((value >> 4) << 8) | (value & 0xf) | (sign ? INDEX_UP : 0);
+	}
       md_number_to_chars (buf, newval, INSN_SIZE);
       break;
 
@@ -21117,7 +21172,7 @@ md_apply_fix (fixS *	fixP,
 	as_bad_where (fixP->fx_file, fixP->fx_line,
 		      _("co-processor offset out of range"));
     cp_off_common:
-      sign = value >= 0;
+      sign = value > 0;
       if (value < 0)
 	value = -value;
       if (fixP->fx_r_type == BFD_RELOC_ARM_CP_OFF_IMM
@@ -21125,8 +21180,13 @@ md_apply_fix (fixS *	fixP,
 	newval = md_chars_to_number (buf, INSN_SIZE);
       else
 	newval = get_thumb32_insn (buf);
-      newval &= 0xff7fff00;
-      newval |= (value >> 2) | (sign ? INDEX_UP : 0);
+      if (value == 0)
+	newval &= 0xffffff00;
+      else
+	{
+	  newval &= 0xff7fff00;
+	  newval |= (value >> 2) | (sign ? INDEX_UP : 0);
+	}
       if (fixP->fx_r_type == BFD_RELOC_ARM_CP_OFF_IMM
 	  || fixP->fx_r_type == BFD_RELOC_ARM_CP_OFF_IMM_S2)
 	md_number_to_chars (buf, newval, INSN_SIZE);
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index 1f54cfe..f7a7079 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,12 @@
+2011-06-02  Jie Zhang <jie@codesourcery.com>
+	    Nathan Sidwell <nathan@codesourcery.com>
+
+	* gas/arm/inst.d: Adjust for signed zero offsets.
+	* gas/arm/ldst-offset0.d: New test.
+	* gas/arm/ldst-offset0.s: New test.
+	* gas/arm/offset-1.d: New test.
+	* gas/arm/offset-1.s: New test.
+
 2011-05-31  Paul Brook  <paul@codesourcery.com>
 
 	* gas/arm/arm-idiv-bad.d: New test.
diff --git a/gas/testsuite/gas/arm/inst.d b/gas/testsuite/gas/arm/inst.d
index e61bbfd..d9bd700 100644
--- a/gas/testsuite/gas/arm/inst.d
+++ b/gas/testsuite/gas/arm/inst.d
@@ -130,7 +130,7 @@ Disassembly of section .text:
 0+1d8 <[^>]*> e6942425 ?	ldr	r2, \[r4\], r5, lsr #8
 0+1dc <[^>]*> e51f0008 ?	ldr	r0, \[pc, #-8\]	; 0+1dc <[^>]*>
 0+1e0 <[^>]*> e5d43000 ?	ldrb	r3, \[r4\]
-0+1e4 <[^>]*> 14f85000 ?	ldrbtne	r5, \[r8\]
+0+1e4 <[^>]*> 14f85000 ?	ldrbtne	r5, \[r8\], #0
 0+1e8 <[^>]*> e5810000 ?	str	r0, \[r1\]
 0+1ec <[^>]*> e7811002 ?	str	r1, \[r1, r2\]
 0+1f0 <[^>]*> e7a43003 ?	str	r3, \[r4, r3\]!
@@ -142,7 +142,7 @@ Disassembly of section .text:
 0+208 <[^>]*> e6a42425 ?	strt	r2, \[r4\], r5, lsr #8
 0+20c <[^>]*> e50f1004 ?	str	r1, \[pc, #-4\]	; 0+210 <[^>]*>
 0+210 <[^>]*> e5c71000 ?	strb	r1, \[r7\]
-0+214 <[^>]*> e4e02000 ?	strbt	r2, \[r0\]
+0+214 <[^>]*> e4e02000 ?	strbt	r2, \[r0\], #0
 0+218 <[^>]*> e8900002 ?	ldm	r0, {r1}
 0+21c <[^>]*> 09920038 ?	ldmibeq	r2, {r3, r4, r5}
 0+220 <[^>]*> e853ffff ?	ldmda	r3, {r0, r1, r2, r3, r4, r5, r6, r7, r8, r9, sl, fp, ip, sp, lr, pc}\^
diff --git a/gas/testsuite/gas/arm/ldst-offset0.d b/gas/testsuite/gas/arm/ldst-offset0.d
new file mode 100644
index 0000000..5c1f88b
--- /dev/null
+++ b/gas/testsuite/gas/arm/ldst-offset0.d
@@ -0,0 +1,51 @@
+#objdump: -dr --prefix-addresses --show-raw-insn
+#name: ARM load/store with 0 offset
+#as:
+
+# Test the standard ARM instructions:
+
+.*: +file format .*arm.*
+
+Disassembly of section .text:
+0+000 <[^>]*> e5121000 	ldr	r1, \[r2, #-0\]
+0+004 <[^>]*> e5121000 	ldr	r1, \[r2, #-0\]
+0+008 <[^>]*> e5921000 	ldr	r1, \[r2\]
+0+00c <[^>]*> e5921000 	ldr	r1, \[r2\]
+0+010 <[^>]*> e5321000 	ldr	r1, \[r2, #-0\]!
+0+014 <[^>]*> e5321000 	ldr	r1, \[r2, #-0\]!
+0+018 <[^>]*> e5b21000 	ldr	r1, \[r2, #0\]!
+0+01c <[^>]*> e5b21000 	ldr	r1, \[r2, #0\]!
+0+020 <[^>]*> e4121000 	ldr	r1, \[r2\], #-0
+0+024 <[^>]*> e4121000 	ldr	r1, \[r2\], #-0
+0+028 <[^>]*> e4921000 	ldr	r1, \[r2\], #0
+0+02c <[^>]*> e4921000 	ldr	r1, \[r2\], #0
+0+030 <[^>]*> e5b21000 	ldr	r1, \[r2, #0\]!
+0+034 <[^>]*> e5921000 	ldr	r1, \[r2\]
+0+038 <[^>]*> e4f21000 	ldrbt	r1, \[r2\], #0
+0+03c <[^>]*> e4721000 	ldrbt	r1, \[r2\], #-0
+0+040 <[^>]*> e4f21000 	ldrbt	r1, \[r2\], #0
+0+044 <[^>]*> 5d565300 	ldclpl	3, cr5, \[r6, #-0\]
+0+048 <[^>]*> 5dd65300 	ldclpl	3, cr5, \[r6\]
+0+04c <[^>]*> e5021000 	str	r1, \[r2, #-0\]
+0+050 <[^>]*> e5021000 	str	r1, \[r2, #-0\]
+0+054 <[^>]*> e5821000 	str	r1, \[r2\]
+0+058 <[^>]*> e5821000 	str	r1, \[r2\]
+0+05c <[^>]*> e5221000 	str	r1, \[r2, #-0\]!
+0+060 <[^>]*> e5221000 	str	r1, \[r2, #-0\]!
+0+064 <[^>]*> e5a21000 	str	r1, \[r2, #0\]!
+0+068 <[^>]*> e5a21000 	str	r1, \[r2, #0\]!
+0+06c <[^>]*> e4021000 	str	r1, \[r2\], #-0
+0+070 <[^>]*> e4021000 	str	r1, \[r2\], #-0
+0+074 <[^>]*> e4821000 	str	r1, \[r2\], #0
+0+078 <[^>]*> e4821000 	str	r1, \[r2\], #0
+0+07c <[^>]*> e5a21000 	str	r1, \[r2, #0\]!
+0+080 <[^>]*> e5821000 	str	r1, \[r2\]
+0+084 <[^>]*> e4e21000 	strbt	r1, \[r2\], #0
+0+088 <[^>]*> e4621000 	strbt	r1, \[r2\], #-0
+0+08c <[^>]*> e4e21000 	strbt	r1, \[r2\], #0
+0+090 <[^>]*> 5d465300 	stclpl	3, cr5, \[r6, #-0\]
+0+094 <[^>]*> 5dc65300 	stclpl	3, cr5, \[r6\]
+0+098 <[^>]*> e59f0004 	ldr	r0, \[pc, #4\]	; .*
+0+09c <[^>]*> e59f0000 	ldr	r0, \[pc\]	; .*
+0+0a0 <[^>]*> e51f0004 	ldr	r0, \[pc, #-4\]	; .*
+0+0a4 <[^>]*> 00000000 	.word	0x00000000
diff --git a/gas/testsuite/gas/arm/ldst-offset0.s b/gas/testsuite/gas/arm/ldst-offset0.s
new file mode 100644
index 0000000..9b0900f
--- /dev/null
+++ b/gas/testsuite/gas/arm/ldst-offset0.s
@@ -0,0 +1,66 @@
+@	Test file for ARM load/store instructions with 0 offset
+
+	.text
+	.syntax unified
+	ldr r1, [r2, #-0]
+	ldr r1, [r2, #-1+1]
+
+	ldr r1, [r2, #1-1]
+	ldr r1, [r2, #0]
+
+	ldr r1, [r2, #-0]!
+	ldr r1, [r2, #-1+1]!
+
+	ldr r1, [r2, #1-1]!
+	ldr r1, [r2, #0]!
+
+	ldr r1, [r2], #-0
+	ldr r1, [r2], #-1+1
+
+	ldr r1, [r2], #1-1
+	ldr r1, [r2], #0
+
+	ldr r1, [r2]!
+	ldr r1, [r2]
+
+	ldrbt r1, [r2], #0
+	ldrbt r1, [r2], #-0
+
+	ldrbt r1, [r2]
+
+	ldclpl p3, c5, [r6, #-0]
+	ldclpl p3, c5, [r6, #0]
+
+	str r1, [r2, #-0]
+	str r1, [r2, #-1+1]
+
+	str r1, [r2, #1-1]
+	str r1, [r2, #0]
+
+	str r1, [r2, #-0]!
+	str r1, [r2, #-1+1]!
+
+	str r1, [r2, #1-1]!
+	str r1, [r2, #0]!
+
+	str r1, [r2], #-0
+	str r1, [r2], #-1+1
+
+	str r1, [r2], #1-1
+	str r1, [r2], #0
+
+	str r1, [r2]!
+	str r1, [r2]
+
+	strbt r1, [r2], #0
+	strbt r1, [r2], #-0
+
+	strbt r1, [r2]
+
+	stclpl p3, c5, [r6, #-0]
+	stclpl p3, c5, [r6, #0]
+
+	ldr	r0,1f
+	ldr	r0,1f
+	ldr	r0,1f
+1:	.word	0
diff --git a/gas/testsuite/gas/arm/offset-1.d b/gas/testsuite/gas/arm/offset-1.d
new file mode 100644
index 0000000..bec9386
--- /dev/null
+++ b/gas/testsuite/gas/arm/offset-1.d
@@ -0,0 +1,23 @@
+# name: MINUS ZERO OFFSET
+# as:
+# objdump: -dr --prefix-addresses --show-raw-insn
+
+.*: +file format .*arm.*
+
+Disassembly of section .text:
+0+00 <[^>]+> e51f0000 ?	ldr	r0, \[pc, #-0\]	; 0+8 <[^>]+>
+0+04 <[^>]+> e59f0000 ?	ldr	r0, \[pc\]	; 0+c <[^>]+>
+0+08 <[^>]+> e5110000 ?	ldr	r0, \[r1, #-0\]
+0+0c <[^>]+> e5910000 ?	ldr	r0, \[r1\]
+0+10 <[^>]+> e4110000 ?	ldr	r0, \[r1\], #-0
+0+14 <[^>]+> e4910000 ?	ldr	r0, \[r1\], #0
+0+18 <[^>]+> e15f00b0 ?	ldrh	r0, \[pc, #-0\]	; 0+20 <[^>]+>
+0+1c <[^>]+> e1df00b0 ?	ldrh	r0, \[pc\]	; 0+24 <[^>]+>
+0+20 <[^>]+> e15100b0 ?	ldrh	r0, \[r1, #-0\]
+0+24 <[^>]+> e1d100b0 ?	ldrh	r0, \[r1\]
+0+28 <[^>]+> e05100b0 ?	ldrh	r0, \[r1\], #-0
+0+2c <[^>]+> e0d100b0 ?	ldrh	r0, \[r1\], #0
+0+30 <[^>]+> e5310000 ?	ldr	r0, \[r1, #-0\]!
+0+34 <[^>]+> e5b10000 ?	ldr	r0, \[r1, #0\]!
+0+38 <[^>]+> e17100b0 ?	ldrh	r0, \[r1, #-0\]!
+0+3c <[^>]+> e1f100b0 ?	ldrh	r0, \[r1, #0\]!
diff --git a/gas/testsuite/gas/arm/offset-1.s b/gas/testsuite/gas/arm/offset-1.s
new file mode 100644
index 0000000..3e99317
--- /dev/null
+++ b/gas/testsuite/gas/arm/offset-1.s
@@ -0,0 +1,16 @@
+	ldr r0, [pc, #-0]
+	ldr r0, [pc, #0]
+	ldr r0, [r1, #-0]
+	ldr r0, [r1, #0]
+	ldr r0, [r1], #-0
+	ldr r0, [r1], #0
+	ldrh r0, [pc, #-0]
+	ldrh r0, [pc, #0]
+	ldrh r0, [r1, #-0]
+	ldrh r0, [r1, #0]
+	ldrh r0, [r1], #-0
+	ldrh r0, [r1], #0
+	ldr r0, [r1, #-0]!
+	ldr r0, [r1, #0]!
+	ldrh r0, [r1, #-0]!
+	ldrh r0, [r1, #0]!