[ARM] Allow MOV/MOV.W to accept all possible immediates

gas/
	* config/tc-arm.c (SBIT_SHIFT): New.
	(T2_SBIT_SHIFT): Likewise.
	(t32_insn_ok): Return TRUE for MOV in ARMv8-M Baseline.
	(md_apply_fix): Try UINT16 encoding when ARM/Thumb modified immediate
	encoding failed.
	* testsuite/gas/arm/archv6t2-bad.s: New error case.
	* testsuite/gas/arm/archv6t2-bad.l: New error match.
	* testsuite/gas/arm/archv6t2.s: New testcase.
	* testsuite/gas/arm/archv6t2.d: New expected result.
	* testsuite/gas/arm/archv8m.s: New testcase.
	* testsuite/gas/arm/archv8m-base.d: New expected result.
	* testsuite/gas/arm/archv8m-main.d: Likewise.
	* testsuite/gas/arm/archv8m-main-dsp-1.d: Likewise.

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 98aa7499558042843e17d93bfdc9f39bb0310f3c..0030ab3f80cf07665086a593564f138f0eec5875 100644 (file)
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,19 @@
+2016-11-02  Jiong Wang  <jiong.wang@arm.com>
+
+       * config/tc-arm.c (SBIT_SHIFT): New.
+       (T2_SBIT_SHIFT): Likewise.
+       (t32_insn_ok): Return TRUE for MOV in ARMv8-M Baseline.
+       (md_apply_fix): Try UINT16 encoding when ARM/Thumb modified immediate
+       encoding failed.
+       * testsuite/gas/arm/archv6t2-bad.s: New error case.
+       * testsuite/gas/arm/archv6t2-bad.l: New error match.
+       * testsuite/gas/arm/archv6t2.s: New testcase.
+       * testsuite/gas/arm/archv6t2.d: New expected result.
+       * testsuite/gas/arm/archv8m.s: New testcase.
+       * testsuite/gas/arm/archv8m-base.d: New expected result.
+       * testsuite/gas/arm/archv8m-main.d: Likewise.
+       * testsuite/gas/arm/archv8m-main-dsp-1.d: Likewise.
+
 2016-11-02  Igor Tsimbalist  <igor.v.tsimbalist@intel.com>
 
        * config/tc-i386.c: (cpu_arch) Add .avx512_4vnniw.

diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c
index 73f8396396ff85276dc5bc92f79764d6d194b3d3..f28bf5297f33d69fd93961aaff51554434ab4223 100644 (file)
--- a/gas/config/tc-arm.c
+++ b/gas/config/tc-arm.c
@@ -685,9 +685,11 @@ struct asm_opcode
 #define T2_SUBS_PC_LR  0xf3de8f00
 
 #define DATA_OP_SHIFT  21
+#define SBIT_SHIFT     20
 
 #define T2_OPCODE_MASK 0xfe1fffff
 #define T2_DATA_OP_SHIFT 21
+#define T2_SBIT_SHIFT   20
 
 #define A_COND_MASK         0xf0000000
 #define A_PUSH_POP_OP_MASK  0x0fff0000
@@ -18270,6 +18272,13 @@ t32_insn_ok (arm_feature_set arch, const struct asm_opcode *opcode)
       && opcode->tencode == do_t_branch)
     return TRUE;
 
+  /* MOV accepts T1/T3 encodings under Baseline, T3 encoding is 32bit.  */
+  if (ARM_CPU_HAS_FEATURE (arch, arm_ext_v8m)
+      && opcode->tencode == do_t_mov_cmp
+      /* Make sure CMP instruction is not affected.  */
+      && opcode->aencode == do_mov)
+    return TRUE;
+
   /* Wide instruction variants of all instructions with narrow *and* wide
      variants become available with ARMv6t2.  Other opcodes are either
      narrow-only or wide-only and are thus available if OPCODE is valid.  */
@@ -22773,6 +22782,23 @@ md_apply_fix (fixS *   fixP,
             changing the opcode.  */
          if (newimm == (unsigned int) FAIL)
            newimm = negate_data_op (&temp, value);
+         /* MOV accepts both ARM modified immediate (A1 encoding) and
+            UINT16 (A2 encoding) when possible, MOVW only accepts UINT16.
+            When disassembling, MOV is preferred when there is no encoding
+            overlap.  */
+         if (newimm == (unsigned int) FAIL
+             && ((temp >> DATA_OP_SHIFT) & 0xf) == OPCODE_MOV
+             && ARM_CPU_HAS_FEATURE (cpu_variant, arm_ext_v6t2)
+             && !((temp >> SBIT_SHIFT) & 0x1)
+             && value >= 0 && value <= 0xffff)
+           {
+             /* Clear bits[23:20] to change encoding from A1 to A2.  */
+             temp &= 0xff0fffff;
+             /* Encoding high 4bits imm.  Code below will encode the remaining
+                low 12bits.  */
+             temp |= (value & 0x0000f000) << 4;
+             newimm = value & 0x00000fff;
+           }
        }
 
       if (newimm == (unsigned int) FAIL)
@@ -23089,32 +23115,59 @@ md_apply_fix (fixS *  fixP,
       newval |= md_chars_to_number (buf+2, THUMB_SIZE);
 
       newimm = FAIL;
-      if (fixP->fx_r_type == BFD_RELOC_ARM_T32_IMMEDIATE
+      if ((fixP->fx_r_type == BFD_RELOC_ARM_T32_IMMEDIATE
+          /* ARMv8-M Baseline MOV will reach here, but it doesn't support
+             Thumb2 modified immediate encoding (T2).  */
+          && ARM_CPU_HAS_FEATURE (cpu_variant, arm_ext_v6t2))
          || fixP->fx_r_type == BFD_RELOC_ARM_T32_ADD_IMM)
        {
          newimm = encode_thumb32_immediate (value);
          if (newimm == (unsigned int) FAIL)
            newimm = thumb32_negate_data_op (&newval, value);
        }
-      if (fixP->fx_r_type != BFD_RELOC_ARM_T32_IMMEDIATE
-         && newimm == (unsigned int) FAIL)
+      if (newimm == (unsigned int) FAIL)
        {
-         /* Turn add/sum into addw/subw.  */
-         if (fixP->fx_r_type == BFD_RELOC_ARM_T32_ADD_IMM)
-           newval = (newval & 0xfeffffff) | 0x02000000;
-         /* No flat 12-bit imm encoding for addsw/subsw.  */
-         if ((newval & 0x00100000) == 0)
+         if (fixP->fx_r_type != BFD_RELOC_ARM_T32_IMMEDIATE)
            {
-             /* 12 bit immediate for addw/subw.  */
-             if (value < 0)
+             /* Turn add/sum into addw/subw.  */
+             if (fixP->fx_r_type == BFD_RELOC_ARM_T32_ADD_IMM)
+               newval = (newval & 0xfeffffff) | 0x02000000;
+             /* No flat 12-bit imm encoding for addsw/subsw.  */
+             if ((newval & 0x00100000) == 0)
                {
-                 value = -value;
-                 newval ^= 0x00a00000;
+                 /* 12 bit immediate for addw/subw.  */
+                 if (value < 0)
+                   {
+                     value = -value;
+                     newval ^= 0x00a00000;
+                   }
+                 if (value > 0xfff)
+                   newimm = (unsigned int) FAIL;
+                 else
+                   newimm = value;
+               }
+           }
+         else
+           {
+             /* MOV accepts both Thumb2 modified immediate (T2 encoding) and
+                UINT16 (T3 encoding), MOVW only accepts UINT16.  When
+                disassembling, MOV is preferred when there is no encoding
+                overlap.
+                NOTE: MOV is using ORR opcode under Thumb 2 mode.  */
+             if (((newval >> T2_DATA_OP_SHIFT) & 0xf) == T2_OPCODE_ORR
+                 && ARM_CPU_HAS_FEATURE (cpu_variant, arm_ext_v6t2_v8m)
+                 && !((newval >> T2_SBIT_SHIFT) & 0x1)
+                 && value >= 0 && value <=0xffff)
+               {
+                 /* Toggle bit[25] to change encoding from T2 to T3.  */
+                 newval ^= 1 << 25;
+                 /* Clear bits[19:16].  */
+                 newval &= 0xfff0ffff;
+                 /* Encoding high 4bits imm.  Code below will encode the
+                    remaining low 12bits.  */
+                 newval |= (value & 0x0000f000) << 4;
+                 newimm = value & 0x00000fff;
                }
-             if (value > 0xfff)
-               newimm = (unsigned int) FAIL;
-             else
-               newimm = value;
            }
        }
 

diff --git a/gas/testsuite/gas/arm/archv6t2-bad.l b/gas/testsuite/gas/arm/archv6t2-bad.l
index 0f00db37b2b826c1a55f194d16b455c7c7421a26..89c28ecd2314c6405eb646f8b29ceeb30f066896 100644 (file)
--- a/gas/testsuite/gas/arm/archv6t2-bad.l
+++ b/gas/testsuite/gas/arm/archv6t2-bad.l
@@ -38,3 +38,4 @@
 [^:]*:53: Warning: source register same as write-back base
 [^:]*:59: Error: instruction does not accept this addressing mode -- `ldrex r0,r2'
 [^:]*:60: Error: instruction does not accept this addressing mode -- `strex r1,r0,r2'
+[^:]*:64: Error: invalid constant \(999\) after fixup

diff --git a/gas/testsuite/gas/arm/archv6t2-bad.s b/gas/testsuite/gas/arm/archv6t2-bad.s
index af1397271b629b0293d728ba1ebd6e5d656b767d..008088d923b6bb29bce440f04c6720735fabedd5 100644 (file)
--- a/gas/testsuite/gas/arm/archv6t2-bad.s
+++ b/gas/testsuite/gas/arm/archv6t2-bad.s
@@ -58,4 +58,7 @@ x:
        @ to a label called "r2".
        ldrex   r0, r2
        strex   r1, r0, r2
-       
\ No newline at end of file
+
+       @ movs shouldn't be extened to accept UINT16 can't fit into ARM modified
+       @ immediate format.
+       movs    r0, #0x0999

diff --git a/gas/testsuite/gas/arm/archv6t2.d b/gas/testsuite/gas/arm/archv6t2.d
index eb76a321a8edfee66b8676cb7b909ac0b3cf4b12..8769b3f3a180f7bb256950b12fc11f0d9e7c2a92 100644 (file)
--- a/gas/testsuite/gas/arm/archv6t2.d
+++ b/gas/testsuite/gas/arm/archv6t2.d
@@ -61,3 +61,4 @@ Disassembly of section .text:
 0+d4 <[^>]+> e06100b2  strht   r0, \[r1\], #-2
 0+d8 <[^>]+> 10e100b2  strhtne r0, \[r1\], #2
 0+dc <[^>]+> 106100b2  strhtne r0, \[r1\], #-2
+0+e0 <[^>]+> e3009999  movw    r9, #2457       ; 0x999

diff --git a/gas/testsuite/gas/arm/archv6t2.s b/gas/testsuite/gas/arm/archv6t2.s
index 81ff5012f5dec6f01cb657ea9e212e9ee07cf1b6..8d74359ad7b430d97af9f7c298198a416033f6b8 100644 (file)
--- a/gas/testsuite/gas/arm/archv6t2.s
+++ b/gas/testsuite/gas/arm/archv6t2.s
@@ -65,3 +65,6 @@ x:
        strht   r0, [r1], #-2
        strneht r0, [r1], #2
        strneht r0, [r1], #-2
+
+       @ mov accept A2 encoding as well.
+       mov     r9, #0x0999

diff --git a/gas/testsuite/gas/arm/archv8m-base.d b/gas/testsuite/gas/arm/archv8m-base.d
index 6a2ee87f3b6eb90754c91c78788276b2bfd92880..6075ee048a077d0a6127607ad7d05fcccaa03cff 100644 (file)
--- a/gas/testsuite/gas/arm/archv8m-base.d
+++ b/gas/testsuite/gas/arm/archv8m-base.d
@@ -16,6 +16,8 @@ Disassembly of section .text:
 0+.* <[^>]*> e849 f840         ttt     r8, r9
 0+.* <[^>]*> f24f 1023         movw    r0, #61731      ; 0xf123
 0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1023         movt    r0, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1823         movt    r8, #61731      ; 0xf123
 0+.* <[^>]*> b154              cbz     r4, 0+.* <[^>]*>

diff --git a/gas/testsuite/gas/arm/archv8m-main-dsp-1.d b/gas/testsuite/gas/arm/archv8m-main-dsp-1.d
index c8f9d7b81bf1af3949afffa7d4d3df7f3065f4bc..8c2c12d0d1cac7ca1b2f8de9abe92aa0802efc81 100644 (file)
--- a/gas/testsuite/gas/arm/archv8m-main-dsp-1.d
+++ b/gas/testsuite/gas/arm/archv8m-main-dsp-1.d
@@ -16,6 +16,8 @@ Disassembly of section .text:
 0+.* <[^>]*> e849 f840         ttt     r8, r9
 0+.* <[^>]*> f24f 1023         movw    r0, #61731      ; 0xf123
 0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1023         movt    r0, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1823         movt    r8, #61731      ; 0xf123
 0+.* <[^>]*> b154              cbz     r4, 0+.* <[^>]*>

diff --git a/gas/testsuite/gas/arm/archv8m-main.d b/gas/testsuite/gas/arm/archv8m-main.d
index a0c40e99c89cef9aaef41c252bc37806d776f278..0b76db10fbda6c972007bb62ff303401f12e506a 100644 (file)
--- a/gas/testsuite/gas/arm/archv8m-main.d
+++ b/gas/testsuite/gas/arm/archv8m-main.d
@@ -16,6 +16,8 @@ Disassembly of section .text:
 0+.* <[^>]*> e849 f840         ttt     r8, r9
 0+.* <[^>]*> f24f 1023         movw    r0, #61731      ; 0xf123
 0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
+0+.* <[^>]*> f24f 1823         movw    r8, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1023         movt    r0, #61731      ; 0xf123
 0+.* <[^>]*> f2cf 1823         movt    r8, #61731      ; 0xf123
 0+.* <[^>]*> b154              cbz     r4, 0+.* <[^>]*>

diff --git a/gas/testsuite/gas/arm/archv8m.s b/gas/testsuite/gas/arm/archv8m.s
index 5f8aafed48746e19056a33405104a9768ed9feab..a82582eb889420177c5ab2afa0e4b555ec6b2047 100644 (file)
--- a/gas/testsuite/gas/arm/archv8m.s
+++ b/gas/testsuite/gas/arm/archv8m.s
@@ -11,6 +11,14 @@ tt    r8, r9
 ttt   r0, r1
 ttt   r8, r9
 movw  r0, #0xF123
+@ mov accept all immediate formats, including T3.  It's also the suggested
+@ assembly to use.
+mov   r8, #0xF123
+@ .w means wide, specifies that the assembler must select a 32-bit encoding for
+@ the instruction if it is possible, it should accept both T2 (Thumb modified
+@ immediate) and T3 (UINT16) encoding.  See the section "Standard assembler
+@ syntax fields" on latest ARM-ARM.
+mov.w r8, #0xF123
 movw  r8, #0xF123
 movt  r0, #0xF123
 movt  r8, #0xF123