[2/2] s390: Optionally print instruction description in disassembly

Message ID 20231208160330.1387610-3-jremus@linux.ibm.com
State Superseded
Headers
Series s390: Optionally print instruction description in disassembly |

Checks

Context Check Description
linaro-tcwg-bot/tcwg_binutils_build--master-arm success Testing passed
linaro-tcwg-bot/tcwg_binutils_build--master-aarch64 success Testing passed
linaro-tcwg-bot/tcwg_binutils_check--master-arm success Testing passed
linaro-tcwg-bot/tcwg_binutils_check--master-aarch64 success Testing passed

Commit Message

Jens Remus Dec. 8, 2023, 4:03 p.m. UTC
  Print instruction description as comment in disassembly with s390
architecture specific option "insndesc":

- For objdump it can be enabled with option "-M insndesc"
- In gdb it can be enabled with "set disassembler-options insndesc"

Since comments are not column aligned the output can enhanced for
readability by postprocessing using a filter such as "expand":

... | expand -t 8,16,24,32,40,80

Or when using in combination with objdump option --visualize-jumps:

... | expand | sed -e 's/ *#/\t#/' | expand -t 1,80

Note that the instruction descriptions add about 128 KB to s390-opc.o:

s390-opc.o without instruction descriptions: 216368 bytes
s390-opc.o with instruction descriptions   : 348432 bytes

binutils/
	* NEWS: Mention new s390-specific disassembler option
	  "insndesc".

include/
	* opcode/s390.h (struct s390_opcode): Add field to hold
	  instruction description.

opcodes/
	* s390-mkopc.c: Copy instruction description from s390-opc.txt
	  into generated operation code table s390-opc.tab.
	* s390-opc.c (s390_opformats): Provide NULL as description in
	  .insn pseudo-mnemonics opcode table.
	* s390-dis.c: Add s390 specific disassembler option "insndesc"
	  and optionally print the instruction description as comment in
	  the disassembly when it is specified.

Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Andreas Krebbel <krebbel@linux.ibm.com>
---
 binutils/NEWS         |  5 ++++
 include/opcode/s390.h |  5 +++-
 opcodes/s390-dis.c    | 13 ++++++++-
 opcodes/s390-mkopc.c  | 18 ++++++++-----
 opcodes/s390-opc.c    | 62 +++++++++++++++++++++----------------------
 5 files changed, 63 insertions(+), 40 deletions(-)
  

Comments

Nick Clifton Dec. 11, 2023, 11:52 a.m. UTC | #1
Hi Jens,

> Print instruction description as comment in disassembly with s390
> architecture specific option "insndesc":

Please could you make one change and, optionally, add one extra feature:


>       int   flags;
> +    char  description[80];

Please could you replace "80" with a #define'd constant, eg MAX_DESC_LEN
and then...


>     op_array[ix].mode_bits = mode_bits;
>     op_array[ix].flags = flags;
> +  strcpy(op_array[ix].description, description);
>     no_ops++;

Use strncpy to ensure that the field is not overwritten by a erroneously
large description.


The optional extra feature is a new test case in the gas testsuite that
makes sure that the new feature actually works... :-)

Cheers
   Nick
  

Patch

diff --git a/binutils/NEWS b/binutils/NEWS
index 73df7053be4..35b84e62b95 100644
--- a/binutils/NEWS
+++ b/binutils/NEWS
@@ -19,6 +19,11 @@ 
 
 * objdump --visualize-jumps is now supported on s390 architecture.
 
+* The s390 disassembly now optionally includes the instruction description as
+  comment with the s390-specific disassembler option "insndesc":
+  - For objdump it can be enabled with "objdump -M insndesc ...".
+  - In gdb it can be enabled with "set disassembler-options insndesc".
+
 Changes in 2.41:
 
 * The MIPS port now supports the Sony Interactive Entertainment Allegrex
diff --git a/include/opcode/s390.h b/include/opcode/s390.h
index d540e1dfd00..319bfe2d629 100644
--- a/include/opcode/s390.h
+++ b/include/opcode/s390.h
@@ -81,7 +81,7 @@  enum s390_opcode_cpu_val
 
 struct s390_opcode
   {
-    /* The opcode name.  */
+    /* The opcode name (mnemonic).  */
     const char * name;
 
     /* The opcode itself.  Those bits which will be filled in with
@@ -110,6 +110,9 @@  struct s390_opcode
 
     /* Instruction specific flags.  */
     unsigned int flags;
+
+    /* Instruction description.  */
+    const char * description;
   };
 
 /* The table itself is sorted by major opcode number, and is otherwise
diff --git a/opcodes/s390-dis.c b/opcodes/s390-dis.c
index 8c8a98c4e24..fca965fbb5d 100644
--- a/opcodes/s390-dis.c
+++ b/opcodes/s390-dis.c
@@ -31,6 +31,7 @@ 
 static int opc_index[256];
 static int current_arch_mask = 0;
 static int option_use_insn_len_bits_p = 0;
+static int option_print_insn_desc = 0;
 
 typedef struct
 {
@@ -43,7 +44,8 @@  static const s390_options_t options[] =
   { "esa" ,       N_("Disassemble in ESA architecture mode") },
   { "zarch",      N_("Disassemble in z/Architecture mode") },
   { "insnlength", N_("Print unknown instructions according to "
-		     "length from first two bits") }
+		     "length from first two bits") },
+  { "insndesc",   N_("Print instruction description as comment") },
 };
 
 /* Set up index table for first opcode byte.  */
@@ -63,6 +65,7 @@  disassemble_init_s390 (struct disassemble_info *info)
 
   current_arch_mask = 1 << S390_OPCODE_ZARCH;
   option_use_insn_len_bits_p = 0;
+  option_print_insn_desc = 0;
 
   for (p = info->disassembler_options; p != NULL; )
     {
@@ -72,6 +75,8 @@  disassemble_init_s390 (struct disassemble_info *info)
 	current_arch_mask = 1 << S390_OPCODE_ZARCH;
       else if (startswith (p, "insnlength"))
 	option_use_insn_len_bits_p = 1;
+      else if (startswith (p, "insndesc"))
+	option_print_insn_desc = 1;
       else
 	/* xgettext:c-format */
 	opcodes_error_handler (_("unknown S/390 disassembler option: %s"), p);
@@ -311,6 +316,12 @@  s390_print_insn_with_opcode (bfd_vma memaddr,
       else
 	separator = ',';
     }
+
+  /* Optional: instruction name.  */
+  if (option_print_insn_desc && opcode->description
+      && opcode->description[0] != '\0')
+    info->fprintf_styled_func (info->stream, dis_style_comment_start, "\t# %s",
+			       opcode->description);
 }
 
 /* Check whether opcode A's mask is more specific than that of B.  */
diff --git a/opcodes/s390-mkopc.c b/opcodes/s390-mkopc.c
index 5f921ee0628..80ffe42978c 100644
--- a/opcodes/s390-mkopc.c
+++ b/opcodes/s390-mkopc.c
@@ -32,6 +32,7 @@  struct op_struct
     int   mode_bits;
     int   min_cpu;
     int   flags;
+    char  description[80];
 
     unsigned long long sort_value;
     int   no_nibbles;
@@ -53,7 +54,7 @@  createTable (void)
 
 static void
 insertOpcode (char *opcode, char *mnemonic, char *format,
-	      int min_cpu, int mode_bits, int flags)
+	      int min_cpu, int mode_bits, int flags, char* description)
 {
   char *str;
   unsigned long long sort_value;
@@ -98,6 +99,7 @@  insertOpcode (char *opcode, char *mnemonic, char *format,
   op_array[ix].min_cpu = min_cpu;
   op_array[ix].mode_bits = mode_bits;
   op_array[ix].flags = flags;
+  strcpy(op_array[ix].description, description);
   no_ops++;
 }
 
@@ -159,7 +161,7 @@  const struct s390_cond_ext_format s390_crb_extensions[NUM_CRB_EXTENSIONS] =
 
 static void
 insertExpandedMnemonic (char *opcode, char *mnemonic, char *format,
-			int min_cpu, int mode_bits, int flags)
+			int min_cpu, int mode_bits, int flags, char *description)
 {
   char *tag;
   char prefix[15];
@@ -172,7 +174,7 @@  insertExpandedMnemonic (char *opcode, char *mnemonic, char *format,
 
   if (!(tag = strpbrk (mnemonic, "*$")))
     {
-      insertOpcode (opcode, mnemonic, format, min_cpu, mode_bits, flags);
+      insertOpcode (opcode, mnemonic, format, min_cpu, mode_bits, flags, description);
       return;
     }
 
@@ -252,7 +254,7 @@  insertExpandedMnemonic (char *opcode, char *mnemonic, char *format,
       opcode[mask_start] = ext_table[i].nibble;
       strcat (new_mnemonic, ext_table[i].extension);
       strcat (new_mnemonic, suffix);
-      insertOpcode (opcode, new_mnemonic, format, min_cpu, mode_bits, flags);
+      insertOpcode (opcode, new_mnemonic, format, min_cpu, mode_bits, flags, description);
     }
   return;
 
@@ -273,7 +275,8 @@  static const char file_header[] =
   "   instruction which matches.\n"
   "   MODE_BITS - zarch or esa\n"
   "   MIN_CPU - number of the min cpu level required\n"
-  "   FLAGS - instruction flags.  */\n\n"
+  "   FLAGS - instruction flags.\n"
+  "   DESCRIPTION - description of the instruction.  */\n\n"
   "const struct s390_opcode s390_opcodes[] =\n  {\n";
 
 /* `dumpTable': write opcode table.  */
@@ -299,7 +302,8 @@  dumpTable (void)
 	      op_array[ix].format, op_array[ix].format);
       printf ("%i, ", op_array[ix].mode_bits);
       printf ("%i, ", op_array[ix].min_cpu);
-      printf ("%i}", op_array[ix].flags);
+      printf ("%i, ", op_array[ix].flags);
+      printf ("\"%s\" }", op_array[ix].description);
       if (ix < no_ops-1)
 	printf (",\n");
       else
@@ -452,7 +456,7 @@  main (void)
 	      str++;
 	  } while (*str != 0);
 	}
-      insertExpandedMnemonic (opcode, mnemonic, format, min_cpu, mode_bits, flag_bits);
+      insertExpandedMnemonic (opcode, mnemonic, format, min_cpu, mode_bits, flag_bits, description);
     }
 
   dumpTable ();
diff --git a/opcodes/s390-opc.c b/opcodes/s390-opc.c
index cbfdb3df0b7..e44621a7479 100644
--- a/opcodes/s390-opc.c
+++ b/opcodes/s390-opc.c
@@ -774,37 +774,37 @@  unused_s390_operands_static_asserts (void)
 
 const struct s390_opcode s390_opformats[] =
   {
-  { "e",    OP8(0x00LL), MASK_E,	   INSTR_E,	      3,  0 ,0 },
-  { "ri",   OP8(0x00LL), MASK_RI_RI,	   INSTR_RI_RI,	      3,  0 ,0 },
-  { "rie",  OP8(0x00LL), MASK_RIE_RRP,	   INSTR_RIE_RRP,     3,  0 ,0 },
-  { "ril",  OP8(0x00LL), MASK_RIL_RP,	   INSTR_RIL_RP,      3,  0 ,0 },
-  { "rilu", OP8(0x00LL), MASK_RIL_RU,	   INSTR_RIL_RU,      3,  0 ,0 },
-  { "ris",  OP8(0x00LL), MASK_RIS_RURDI,   INSTR_RIS_RURDI,   3,  6 ,0 },
-  { "rr",   OP8(0x00LL), MASK_RR_RR,	   INSTR_RR_RR,       3,  0 ,0 },
-  { "rre",  OP8(0x00LL), MASK_RRE_RR,	   INSTR_RRE_RR,      3,  0 ,0 },
-  { "rrf",  OP8(0x00LL), MASK_RRF_RURR,	   INSTR_RRF_RURR,    3,  0 ,0 },
-  { "rrs",  OP8(0x00LL), MASK_RRS_RRRDU,   INSTR_RRS_RRRDU,   3,  6 ,0 },
-  { "rs",   OP8(0x00LL), MASK_RS_RRRD,	   INSTR_RS_RRRD,     3,  0 ,0 },
-  { "rse",  OP8(0x00LL), MASK_RSE_RRRD,	   INSTR_RSE_RRRD,    3,  0 ,0 },
-  { "rsi",  OP8(0x00LL), MASK_RSI_RRP,	   INSTR_RSI_RRP,     3,  0 ,0 },
-  { "rsy",  OP8(0x00LL), MASK_RSY_RRRD,	   INSTR_RSY_RRRD,    3,  3 ,0 },
-  { "rx",   OP8(0x00LL), MASK_RX_RRRD,	   INSTR_RX_RRRD,     3,  0 ,0 },
-  { "rxe",  OP8(0x00LL), MASK_RXE_RRRD,	   INSTR_RXE_RRRD,    3,  0 ,0 },
-  { "rxf",  OP8(0x00LL), MASK_RXF_RRRDR,   INSTR_RXF_RRRDR,   3,  0 ,0 },
-  { "rxy",  OP8(0x00LL), MASK_RXY_RRRD,	   INSTR_RXY_RRRD,    3,  3 ,0 },
-  { "s",    OP8(0x00LL), MASK_S_RD,	   INSTR_S_RD,	      3,  0 ,0 },
-  { "si",   OP8(0x00LL), MASK_SI_URD,	   INSTR_SI_URD,      3,  0 ,0 },
-  { "siy",  OP8(0x00LL), MASK_SIY_URD,	   INSTR_SIY_URD,     3,  3 ,0 },
-  { "sil",  OP8(0x00LL), MASK_SIL_RDI,     INSTR_SIL_RDI,     3,  6 ,0 },
-  { "ss",   OP8(0x00LL), MASK_SS_RRRDRD,   INSTR_SS_RRRDRD,   3,  0 ,0 },
-  { "sse",  OP8(0x00LL), MASK_SSE_RDRD,	   INSTR_SSE_RDRD,    3,  0 ,0 },
-  { "ssf",  OP8(0x00LL), MASK_SSF_RRDRD,   INSTR_SSF_RRDRD,   3,  0 ,0 },
-  { "vrv",  OP8(0x00LL), MASK_VRV_VVXRDU,  INSTR_VRV_VVXRDU,  3,  9 ,0 },
-  { "vri",  OP8(0x00LL), MASK_VRI_VVUUU,   INSTR_VRI_VVUUU,   3,  9 ,0 },
-  { "vrx",  OP8(0x00LL), MASK_VRX_VRRDU,   INSTR_VRX_VRRDU,   3,  9 ,0 },
-  { "vrs",  OP8(0x00LL), MASK_VRS_RVRDU,   INSTR_VRS_RVRDU,   3,  9 ,0 },
-  { "vrr",  OP8(0x00LL), MASK_VRR_VVV0UUU, INSTR_VRR_VVV0UUU, 3,  9 ,0 },
-  { "vsi",  OP8(0x00LL), MASK_VSI_URDV,	   INSTR_VSI_URDV,    3, 10 ,0 },
+  { "e",    OP8(0x00LL), MASK_E,	   INSTR_E,	      3,  0, 0, NULL },
+  { "ri",   OP8(0x00LL), MASK_RI_RI,	   INSTR_RI_RI,	      3,  0, 0, NULL },
+  { "rie",  OP8(0x00LL), MASK_RIE_RRP,	   INSTR_RIE_RRP,     3,  0, 0, NULL },
+  { "ril",  OP8(0x00LL), MASK_RIL_RP,	   INSTR_RIL_RP,      3,  0, 0, NULL },
+  { "rilu", OP8(0x00LL), MASK_RIL_RU,	   INSTR_RIL_RU,      3,  0, 0, NULL },
+  { "ris",  OP8(0x00LL), MASK_RIS_RURDI,   INSTR_RIS_RURDI,   3,  6, 0, NULL },
+  { "rr",   OP8(0x00LL), MASK_RR_RR,	   INSTR_RR_RR,       3,  0, 0, NULL },
+  { "rre",  OP8(0x00LL), MASK_RRE_RR,	   INSTR_RRE_RR,      3,  0, 0, NULL },
+  { "rrf",  OP8(0x00LL), MASK_RRF_RURR,	   INSTR_RRF_RURR,    3,  0, 0, NULL },
+  { "rrs",  OP8(0x00LL), MASK_RRS_RRRDU,   INSTR_RRS_RRRDU,   3,  6, 0, NULL },
+  { "rs",   OP8(0x00LL), MASK_RS_RRRD,	   INSTR_RS_RRRD,     3,  0, 0, NULL },
+  { "rse",  OP8(0x00LL), MASK_RSE_RRRD,	   INSTR_RSE_RRRD,    3,  0, 0, NULL },
+  { "rsi",  OP8(0x00LL), MASK_RSI_RRP,	   INSTR_RSI_RRP,     3,  0, 0, NULL },
+  { "rsy",  OP8(0x00LL), MASK_RSY_RRRD,	   INSTR_RSY_RRRD,    3,  3, 0, NULL },
+  { "rx",   OP8(0x00LL), MASK_RX_RRRD,	   INSTR_RX_RRRD,     3,  0, 0, NULL },
+  { "rxe",  OP8(0x00LL), MASK_RXE_RRRD,	   INSTR_RXE_RRRD,    3,  0, 0, NULL },
+  { "rxf",  OP8(0x00LL), MASK_RXF_RRRDR,   INSTR_RXF_RRRDR,   3,  0, 0, NULL },
+  { "rxy",  OP8(0x00LL), MASK_RXY_RRRD,	   INSTR_RXY_RRRD,    3,  3, 0, NULL },
+  { "s",    OP8(0x00LL), MASK_S_RD,	   INSTR_S_RD,	      3,  0, 0, NULL },
+  { "si",   OP8(0x00LL), MASK_SI_URD,	   INSTR_SI_URD,      3,  0, 0, NULL },
+  { "siy",  OP8(0x00LL), MASK_SIY_URD,	   INSTR_SIY_URD,     3,  3, 0, NULL },
+  { "sil",  OP8(0x00LL), MASK_SIL_RDI,     INSTR_SIL_RDI,     3,  6, 0, NULL },
+  { "ss",   OP8(0x00LL), MASK_SS_RRRDRD,   INSTR_SS_RRRDRD,   3,  0, 0, NULL },
+  { "sse",  OP8(0x00LL), MASK_SSE_RDRD,	   INSTR_SSE_RDRD,    3,  0, 0, NULL },
+  { "ssf",  OP8(0x00LL), MASK_SSF_RRDRD,   INSTR_SSF_RRDRD,   3,  0, 0, NULL },
+  { "vrv",  OP8(0x00LL), MASK_VRV_VVXRDU,  INSTR_VRV_VVXRDU,  3,  9, 0, NULL },
+  { "vri",  OP8(0x00LL), MASK_VRI_VVUUU,   INSTR_VRI_VVUUU,   3,  9, 0, NULL },
+  { "vrx",  OP8(0x00LL), MASK_VRX_VRRDU,   INSTR_VRX_VRRDU,   3,  9, 0, NULL },
+  { "vrs",  OP8(0x00LL), MASK_VRS_RVRDU,   INSTR_VRS_RVRDU,   3,  9, 0, NULL },
+  { "vrr",  OP8(0x00LL), MASK_VRR_VVV0UUU, INSTR_VRR_VVV0UUU, 3,  9, 0, NULL },
+  { "vsi",  OP8(0x00LL), MASK_VSI_URDV,	   INSTR_VSI_URDV,    3, 10, 0, NULL },
 };
 
 const int s390_num_opformats =