opcodes/aarch64: split off creation of comment text in disassembler

The function aarch64_print_operand (aarch64-opc.c) is responsible for
converting an instruction operand into the textual representation of
that operand.

In some cases, a comment is included in the operand representation,
though this (currently) only happens for the last operand of the
instruction.

In a future commit I would like to enable the new libopcodes styling
for AArch64, this will allow objdump and GDB[1] to syntax highlight
the disassembler output, however, having operands and comments
combined in a single string like this makes such styling harder.

In this commit, I propose to extend aarch64_print_operand to take a
second buffer.  Any comments for the instruction are written into this
extra buffer.  The two callers of aarch64_print_operand are then
updated to pass an extra buffer, and print any resulting comment.

In this commit no styling is added, that will come later.  However, I
have adjusted the output slightly.  Before this commit some comments
would be separated from the instruction operands with a tab character,
while in other cases the comment was separated with two single spaces.

After this commit I use a single tab character in all cases.  This
means a few test cases needed updated.  If people would prefer me to
move everyone to use the two spaces, then just let me know.  Or maybe
there was a good reason why we used a mix of styles, I could probably
figure out a way to maintain the old output exactly if that is
critical.

Other than that, there should be no user visible changes after this
commit.

[1] GDB patches have not been merged yet, but have been posted to the
GDB mailing list:
https://sourceware.org/pipermail/gdb-patches/2022-June/190142.html

diff --git a/gas/config/tc-aarch64.c b/gas/config/tc-aarch64.c
index e9f7ee9fc964c3716474b04316d992be846dfbb5..779db31828bf93d75f7e8eb088f80793eca493a2 100644 (file)
--- a/gas/config/tc-aarch64.c
+++ b/gas/config/tc-aarch64.c
@@ -5358,6 +5358,7 @@ print_operands (char *buf, const aarch64_opcode *opcode,
   for (i = 0; i < AARCH64_MAX_OPND_NUM; ++i)
     {
       char str[128];
+      char cmt[128];
 
       /* We regard the opcode operand info more, however we also look into
         the inst->operands to support the disassembling of the optional
@@ -5370,7 +5371,7 @@ print_operands (char *buf, const aarch64_opcode *opcode,
 
       /* Generate the operand string in STR.  */
       aarch64_print_operand (str, sizeof (str), 0, opcode, opnds, i, NULL, NULL,
-                            NULL, cpu_variant);
+                            NULL, cmt, sizeof (cmt), cpu_variant);
 
       /* Delimiter.  */
       if (str[0] != '\0')
@@ -5378,6 +5379,15 @@ print_operands (char *buf, const aarch64_opcode *opcode,
 
       /* Append the operand string.  */
       strcat (buf, str);
+
+      /* Append a comment.  This works because only the last operand ever
+        adds a comment.  If that ever changes then we'll need to be
+        smarter here.  */
+      if (cmt[0] != '\0')
+       {
+         strcat (buf, "\t// ");
+         strcat (buf, cmt);
+       }
     }
 }
 

diff --git a/gas/testsuite/gas/aarch64/alias.d b/gas/testsuite/gas/aarch64/alias.d
index 13b943c1b9761ffd1d162df69aa1f902e5e8b37c..b1d1a9a37c26d67ca74acf3489e84080d4d73f92 100644 (file)
--- a/gas/testsuite/gas/aarch64/alias.d
+++ b/gas/testsuite/gas/aarch64/alias.d
@@ -29,19 +29,19 @@ Disassembly of section \.text:
   54:  9ba28c20        umsubl  x0, w1, w2, x3
   58:  9ba2fc20        umnegl  x0, w1, w2
   5c:  9ba2fc20        umnegl  x0, w1, w2
-  60:  1a9f0420        csinc   w0, w1, wzr, eq  // eq = none
-  64:  1a810420        cinc    w0, w1, ne  // ne = any
-  68:  1a810420        cinc    w0, w1, ne  // ne = any
-  6c:  1a9f37e0        cset    w0, cs  // cs = hs, nlast
-  70:  1a9f37e0        cset    w0, cs  // cs = hs, nlast
-  74:  da9f2020        csinv   x0, x1, xzr, cs  // cs = hs, nlast
-  78:  da812020        cinv    x0, x1, cc  // cc = lo, ul, last
-  7c:  da812020        cinv    x0, x1, cc  // cc = lo, ul, last
-  80:  da9f43e0        csetm   x0, pl  // pl = nfrst
-  84:  da9f43e0        csetm   x0, pl  // pl = nfrst
-  88:  da9eb7e0        csneg   x0, xzr, x30, lt  // lt = tstop
-  8c:  da9eb7c0        cneg    x0, x30, ge  // ge = tcont
-  90:  da9eb7c0        cneg    x0, x30, ge  // ge = tcont
+  60:  1a9f0420        csinc   w0, w1, wzr, eq // eq = none
+  64:  1a810420        cinc    w0, w1, ne      // ne = any
+  68:  1a810420        cinc    w0, w1, ne      // ne = any
+  6c:  1a9f37e0        cset    w0, cs  // cs = hs, nlast
+  70:  1a9f37e0        cset    w0, cs  // cs = hs, nlast
+  74:  da9f2020        csinv   x0, x1, xzr, cs // cs = hs, nlast
+  78:  da812020        cinv    x0, x1, cc      // cc = lo, ul, last
+  7c:  da812020        cinv    x0, x1, cc      // cc = lo, ul, last
+  80:  da9f43e0        csetm   x0, pl  // pl = nfrst
+  84:  da9f43e0        csetm   x0, pl  // pl = nfrst
+  88:  da9eb7e0        csneg   x0, xzr, x30, lt        // lt = tstop
+  8c:  da9eb7c0        cneg    x0, x30, ge     // ge = tcont
+  90:  da9eb7c0        cneg    x0, x30, ge     // ge = tcont
   94:  ea020020        ands    x0, x1, x2
   98:  ea02003f        tst     x1, x2
   9c:  ea02003f        tst     x1, x2

diff --git a/gas/testsuite/gas/aarch64/b_c_1.d b/gas/testsuite/gas/aarch64/b_c_1.d
index 6427a3a63a5cc459953b3f770fa64162bdf67475..f9359a4842c1271ec19e15a76c3de4061cc8ffd9 100644 (file)
--- a/gas/testsuite/gas/aarch64/b_c_1.d
+++ b/gas/testsuite/gas/aarch64/b_c_1.d
@@ -31,28 +31,28 @@ Disassembly of section \.text:
 .*:    54.....b        b\.lt   0 <\.text>  // b\.tstop
 .*:    54.....c        b\.gt   0 <\.text>
 .*:    54.....d        b\.le   0 <\.text>
-.*:    9a830041        csel    x1, x2, x3, eq  // eq = none
-.*:    9a830041        csel    x1, x2, x3, eq  // eq = none
-.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
-.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
-.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
-.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
-.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
-.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
-.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
-.*:    9a834041        csel    x1, x2, x3, mi  // mi = first
-.*:    9a834041        csel    x1, x2, x3, mi  // mi = first
-.*:    9a835041        csel    x1, x2, x3, pl  // pl = nfrst
-.*:    9a835041        csel    x1, x2, x3, pl  // pl = nfrst
+.*:    9a830041        csel    x1, x2, x3, eq  // eq = none
+.*:    9a830041        csel    x1, x2, x3, eq  // eq = none
+.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
+.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
+.*:    9a832041        csel    x1, x2, x3, cs  // cs = hs, nlast
+.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
+.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
+.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
+.*:    9a833041        csel    x1, x2, x3, cc  // cc = lo, ul, last
+.*:    9a834041        csel    x1, x2, x3, mi  // mi = first
+.*:    9a834041        csel    x1, x2, x3, mi  // mi = first
+.*:    9a835041        csel    x1, x2, x3, pl  // pl = nfrst
+.*:    9a835041        csel    x1, x2, x3, pl  // pl = nfrst
 .*:    9a836041        csel    x1, x2, x3, vs
 .*:    9a837041        csel    x1, x2, x3, vc
-.*:    9a838041        csel    x1, x2, x3, hi  // hi = pmore
-.*:    9a838041        csel    x1, x2, x3, hi  // hi = pmore
-.*:    9a839041        csel    x1, x2, x3, ls  // ls = plast
-.*:    9a839041        csel    x1, x2, x3, ls  // ls = plast
-.*:    9a83a041        csel    x1, x2, x3, ge  // ge = tcont
-.*:    9a83a041        csel    x1, x2, x3, ge  // ge = tcont
-.*:    9a83b041        csel    x1, x2, x3, lt  // lt = tstop
-.*:    9a83b041        csel    x1, x2, x3, lt  // lt = tstop
+.*:    9a838041        csel    x1, x2, x3, hi  // hi = pmore
+.*:    9a838041        csel    x1, x2, x3, hi  // hi = pmore
+.*:    9a839041        csel    x1, x2, x3, ls  // ls = plast
+.*:    9a839041        csel    x1, x2, x3, ls  // ls = plast
+.*:    9a83a041        csel    x1, x2, x3, ge  // ge = tcont
+.*:    9a83a041        csel    x1, x2, x3, ge  // ge = tcont
+.*:    9a83b041        csel    x1, x2, x3, lt  // lt = tstop
+.*:    9a83b041        csel    x1, x2, x3, lt  // lt = tstop
 .*:    9a83c041        csel    x1, x2, x3, gt
 .*:    9a83d041        csel    x1, x2, x3, le

diff --git a/gas/testsuite/gas/aarch64/float-fp16.d b/gas/testsuite/gas/aarch64/float-fp16.d
index d1d69d820f05b35efa182cbd15eac553a4d6cfdd..3d96a45a80cc4ef1214edf52bfbe21f5d1bdad8c 100644 (file)
--- a/gas/testsuite/gas/aarch64/float-fp16.d
+++ b/gas/testsuite/gas/aarch64/float-fp16.d
@@ -6,12 +6,12 @@
 Disassembly of section \.text:
 
 0+ <.*>:
-   [0-9a-f]+:  1e200400        fccmp   s0, s0, #0x0, eq  // eq = none
-   [0-9a-f]+:  1ee00400        fccmp   h0, h0, #0x0, eq  // eq = none
+   [0-9a-f]+:  1e200400        fccmp   s0, s0, #0x0, eq        // eq = none
+   [0-9a-f]+:  1ee00400        fccmp   h0, h0, #0x0, eq        // eq = none
    [0-9a-f]+:  1e22d420        fccmp   s1, s2, #0x0, le
    [0-9a-f]+:  1ee2d420        fccmp   h1, h2, #0x0, le
-  [0-9a-f]+:   1e200410        fccmpe  s0, s0, #0x0, eq  // eq = none
-  [0-9a-f]+:   1ee00410        fccmpe  h0, h0, #0x0, eq  // eq = none
+  [0-9a-f]+:   1e200410        fccmpe  s0, s0, #0x0, eq        // eq = none
+  [0-9a-f]+:   1ee00410        fccmpe  h0, h0, #0x0, eq        // eq = none
   [0-9a-f]+:   1e22d430        fccmpe  s1, s2, #0x0, le
   [0-9a-f]+:   1ee2d430        fccmpe  h1, h2, #0x0, le
   [0-9a-f]+:   1e202000        fcmp    s0, s0
@@ -26,8 +26,8 @@ Disassembly of section \.text:
   [0-9a-f]+:   1ee02008        fcmp    h0, #0\.0
   [0-9a-f]+:   1e202018        fcmpe   s0, #0\.0
   [0-9a-f]+:   1ee02018        fcmpe   h0, #0\.0
-  [0-9a-f]+:   1e210c00        fcsel   s0, s0, s1, eq  // eq = none
-  [0-9a-f]+:   1ee10c00        fcsel   h0, h0, h1, eq  // eq = none
+  [0-9a-f]+:   1e210c00        fcsel   s0, s0, s1, eq  // eq = none
+  [0-9a-f]+:   1ee10c00        fcsel   h0, h0, h1, eq  // eq = none
   [0-9a-f]+:   9ee60000        fmov    x0, h0
   [0-9a-f]+:   1ee60000        fmov    w0, h0
   [0-9a-f]+:   9ee70001        fmov    h1, x0

diff --git a/gas/testsuite/gas/aarch64/int-insns.d b/gas/testsuite/gas/aarch64/int-insns.d
index 419b8a6e84175f5cca08fa4483534e8660cbeb4b..76f937c4fbf82ad6b7431efa3b441e2e54c7068a 100644 (file)
--- a/gas/testsuite/gas/aarch64/int-insns.d
+++ b/gas/testsuite/gas/aarch64/int-insns.d
@@ -13,8 +13,8 @@ Disassembly of section .text:
   10:  93c3fc41        extr    x1, x2, x3, #63
   14:  93c30041        extr    x1, x2, x3, #0
   18:  13837c41        extr    w1, w2, w3, #31
-  1c:  9a9f17e1        cset    x1, eq  // eq = none
-  20:  da9f13e1        csetm   x1, eq  // eq = none
+  1c:  9a9f17e1        cset    x1, eq  // eq = none
+  20:  da9f13e1        csetm   x1, eq  // eq = none
   24:  71000021        subs    w1, w1, #0x0
   28:  7100003f        cmp     w1, #0x0
   2c:  4b0203e1        neg     w1, w2

diff --git a/gas/testsuite/gas/aarch64/no-aliases.d b/gas/testsuite/gas/aarch64/no-aliases.d
index dae0b712dab3c2a014ead788bc9ecd8678986959..3cee28df657bf46e6ba248e085cde3500b4c5673 100644 (file)
--- a/gas/testsuite/gas/aarch64/no-aliases.d
+++ b/gas/testsuite/gas/aarch64/no-aliases.d
@@ -30,19 +30,19 @@ Disassembly of section \.text:
   54:  9ba28c20        umsubl  x0, w1, w2, x3
   58:  9ba2fc20        umsubl  x0, w1, w2, xzr
   5c:  9ba2fc20        umsubl  x0, w1, w2, xzr
-  60:  1a9f0420        csinc   w0, w1, wzr, eq  // eq = none
-  64:  1a810420        csinc   w0, w1, w1, eq  // eq = none
-  68:  1a810420        csinc   w0, w1, w1, eq  // eq = none
-  6c:  1a9f37e0        csinc   w0, wzr, wzr, cc  // cc = lo, ul, last
-  70:  1a9f37e0        csinc   w0, wzr, wzr, cc  // cc = lo, ul, last
-  74:  da9f2020        csinv   x0, x1, xzr, cs  // cs = hs, nlast
-  78:  da812020        csinv   x0, x1, x1, cs  // cs = hs, nlast
-  7c:  da812020        csinv   x0, x1, x1, cs  // cs = hs, nlast
-  80:  da9f43e0        csinv   x0, xzr, xzr, mi  // mi = first
-  84:  da9f43e0        csinv   x0, xzr, xzr, mi  // mi = first
-  88:  da9eb7e0        csneg   x0, xzr, x30, lt  // lt = tstop
-  8c:  da9eb7c0        csneg   x0, x30, x30, lt  // lt = tstop
-  90:  da9eb7c0        csneg   x0, x30, x30, lt  // lt = tstop
+  60:  1a9f0420        csinc   w0, w1, wzr, eq // eq = none
+  64:  1a810420        csinc   w0, w1, w1, eq  // eq = none
+  68:  1a810420        csinc   w0, w1, w1, eq  // eq = none
+  6c:  1a9f37e0        csinc   w0, wzr, wzr, cc        // cc = lo, ul, last
+  70:  1a9f37e0        csinc   w0, wzr, wzr, cc        // cc = lo, ul, last
+  74:  da9f2020        csinv   x0, x1, xzr, cs // cs = hs, nlast
+  78:  da812020        csinv   x0, x1, x1, cs  // cs = hs, nlast
+  7c:  da812020        csinv   x0, x1, x1, cs  // cs = hs, nlast
+  80:  da9f43e0        csinv   x0, xzr, xzr, mi        // mi = first
+  84:  da9f43e0        csinv   x0, xzr, xzr, mi        // mi = first
+  88:  da9eb7e0        csneg   x0, xzr, x30, lt        // lt = tstop
+  8c:  da9eb7c0        csneg   x0, x30, x30, lt        // lt = tstop
+  90:  da9eb7c0        csneg   x0, x30, x30, lt        // lt = tstop
   94:  ea020020        ands    x0, x1, x2
   98:  ea02003f        ands    xzr, x1, x2
   9c:  ea02003f        ands    xzr, x1, x2

diff --git a/gas/testsuite/gas/aarch64/programmer-friendly.d b/gas/testsuite/gas/aarch64/programmer-friendly.d
index 668a13506fb7d401e903e27a561c200b5e364533..8fa6aa70dbf13e2ddb105b5d0f8339b261785b79 100644 (file)
--- a/gas/testsuite/gas/aarch64/programmer-friendly.d
+++ b/gas/testsuite/gas/aarch64/programmer-friendly.d
@@ -10,7 +10,7 @@ Disassembly of section \.text:
    4:  98000241        ldrsw   x1, 4c <\.text\+0x4c>
    8:  98000007        ldrsw   x7, 0 <\.text>
                        8: R_AARCH64_LD_PREL_LO19       \.data\+0x4
-   c:  fa42a02a        ccmp    x1, x2, #0xa, ge  // ge = tcont
+   c:  fa42a02a        ccmp    x1, x2, #0xa, ge        // ge = tcont
   10:  53001eaf        uxtb    w15, w21
   14:  53003f67        uxth    w7, w27
   18:  2a1f03e8        mov     w8, wzr

diff --git a/include/opcode/aarch64.h b/include/opcode/aarch64.h
index 8fe27900cba3e897880a3966cc2a17e89dbdf018..186ba9a4800c994138aadb5b0258c8fa50732d32 100644 (file)
--- a/include/opcode/aarch64.h
+++ b/include/opcode/aarch64.h
@@ -1371,7 +1371,7 @@ aarch64_get_opcode (enum aarch64_op);
 extern void
 aarch64_print_operand (char *, size_t, bfd_vma, const aarch64_opcode *,
                       const aarch64_opnd_info *, int, int *, bfd_vma *,
-                      char **,
+                      char **, char *, size_t,
                       aarch64_feature_set features);
 
 /* Miscellaneous interface.  */

diff --git a/opcodes/aarch64-dis.c b/opcodes/aarch64-dis.c
index bd2068b0f32f343f5bb48ee4c30dc996a4232d6c..acaad28fdffd61d111aa3dcf5ced598f92209038 100644 (file)
--- a/opcodes/aarch64-dis.c
+++ b/opcodes/aarch64-dis.c
@@ -3287,6 +3287,8 @@ print_operands (bfd_vma pc, const aarch64_opcode *opcode,
   for (i = 0, num_printed = 0; i < AARCH64_MAX_OPND_NUM; ++i)
     {
       char str[128];
+      char cmt[128];
+
       /* We regard the opcode operand info more, however we also look into
         the inst->operands to support the disassembling of the optional
         operand.
@@ -3298,7 +3300,8 @@ print_operands (bfd_vma pc, const aarch64_opcode *opcode,
 
       /* Generate the operand string in STR.  */
       aarch64_print_operand (str, sizeof (str), pc, opcode, opnds, i, &pcrel_p,
-                            &info->target, &notes, arch_variant);
+                            &info->target, &notes, cmt, sizeof (cmt),
+                            arch_variant);
 
       /* Print the delimiter (taking account of omitted operand(s)).  */
       if (str[0] != '\0')
@@ -3309,7 +3312,15 @@ print_operands (bfd_vma pc, const aarch64_opcode *opcode,
       if (pcrel_p)
        (*info->print_address_func) (info->target, info);
       else
-       (*info->fprintf_func) (info->stream, "%s", str);
+       {
+         (*info->fprintf_func) (info->stream, "%s", str);
+
+         /* Print the comment.  This works because only the last operand
+            ever adds a comment.  If that ever changes then we'll need to
+            be smarter here.  */
+         if (cmt[0] != '\0')
+           (*info->fprintf_func) (info->stream, "\t// %s", cmt);
+       }
     }
 
     if (notes && !no_notes)

diff --git a/opcodes/aarch64-opc.c b/opcodes/aarch64-opc.c
index 37f6dae07ad22d1e216193ddf499c10042d19f76..1c93f8360204524e7318668265359d56845068f4 100644 (file)
--- a/opcodes/aarch64-opc.c
+++ b/opcodes/aarch64-opc.c
@@ -3229,6 +3229,7 @@ aarch64_print_operand (char *buf, size_t size, bfd_vma pc,
                       const aarch64_opcode *opcode,
                       const aarch64_opnd_info *opnds, int idx, int *pcrel_p,
                       bfd_vma *address, char** notes,
+                      char *comment, size_t comment_size,
                       aarch64_feature_set features)
 {
   unsigned int i, num_conds;
@@ -3237,6 +3238,14 @@ aarch64_print_operand (char *buf, size_t size, bfd_vma pc,
   enum aarch64_modifier_kind kind;
   uint64_t addr, enum_value;
 
+  if (comment != NULL)
+    {
+      assert (comment_size > 0);
+      comment[0] = '\0';
+    }
+  else
+    assert (comment_size == 0);
+
   buf[0] = '\0';
   if (pcrel_p)
     *pcrel_p = 0;
@@ -3572,12 +3581,13 @@ aarch64_print_operand (char *buf, size_t size, bfd_vma pc,
        case 4: /* e.g. MOV Wd, #<imm32>.  */
            {
              int imm32 = opnd->imm.value;
-             snprintf (buf, size, "#0x%-20x\t// #%d", imm32, imm32);
+             snprintf (buf, size, "#0x%-20x", imm32);
+             snprintf (comment, comment_size, "#%d", imm32);
            }
          break;
        case 8: /* e.g. MOV Xd, #<imm64>.  */
-         snprintf (buf, size, "#0x%-20" PRIx64 "\t// #%" PRIi64,
-                   opnd->imm.value, opnd->imm.value);
+         snprintf (buf, size, "#0x%-20" PRIx64, opnd->imm.value);
+         snprintf (comment, comment_size, "#%" PRIi64, opnd->imm.value);
          break;
        default:
          snprintf (buf, size, "<invalid>");
@@ -3675,12 +3685,12 @@ aarch64_print_operand (char *buf, size_t size, bfd_vma pc,
       num_conds = ARRAY_SIZE (opnd->cond->names);
       for (i = 1; i < num_conds && opnd->cond->names[i]; ++i)
        {
-         size_t len = strlen (buf);
+         size_t len = comment != NULL ? strlen (comment) : 0;
          if (i == 1)
-           snprintf (buf + len, size - len, "  // %s = %s",
+           snprintf (comment + len, comment_size - len, "%s = %s",
                      opnd->cond->names[0], opnd->cond->names[i]);
          else
-           snprintf (buf + len, size - len, ", %s",
+           snprintf (comment + len, comment_size - len, ", %s",
                      opnd->cond->names[i]);
        }
       break;