Correct handling of constant fields.

	* gen.c (insn_field_cmp): Tweak comment about neither field
	being an insn_field_string with a cond_eq-to-value condition.
	(insns_bit_useless) <case insn_field_string, case
	decode_find_mixed>: Handle cond_eq-to-value fields as
	insn_field_int.
	* gen-idecode.c (print_idecode_validate): Handle
	insn_field_string cond-equal-to-value fields as insn_field_int.
	* gen-icache.c (print_icache_body): Add comment why constant
	string fields are handled.

diff --git a/sim/igen/ChangeLog b/sim/igen/ChangeLog
index 576962e3d9083b4086f8340f2fd0ea583f0bdb7f..7b14eee4de902dbc6ccd8460cbb1ccc4296f7dcf 100644 (file)
--- a/sim/igen/ChangeLog
+++ b/sim/igen/ChangeLog
@@ -1,5 +1,16 @@
 2011-07-08  Hans-Peter Nilsson  <hp@axis.com>
 
+       Correct handling of constant fields.
+       * gen.c (insn_field_cmp): Tweak comment about neither field
+       being an insn_field_string with a cond_eq-to-value condition.
+       (insns_bit_useless) <case insn_field_string, case
+       decode_find_mixed>: Handle cond_eq-to-value fields as
+       insn_field_int.
+       * gen-idecode.c (print_idecode_validate): Handle
+       insn_field_string cond-equal-to-value fields as insn_field_int.
+       * gen-icache.c (print_icache_body): Add comment why constant
+       string fields are handled.
+
        Remove all #if 0'd code.
        * filter.c: Remove #if 0'd function it_is.
        (main): Remove #if 0'd code.

diff --git a/sim/igen/gen-icache.c b/sim/igen/gen-icache.c
index b6fc43c0f040199df13d0b441b6b18696114e313..783765b0dee86a993793762d4af016885d16331c 100644 (file)
--- a/sim/igen/gen-icache.c
+++ b/sim/igen/gen-icache.c
@@ -424,6 +424,8 @@ print_icache_body (lf *file,
             cur_field->first < options.insn_bit_size;
             cur_field = cur_field->next)
          {
+           /* Always expand named fields (even if constant), so
+              references are valid.  */
            if (cur_field->type == insn_field_string)
              {
                cache_entry *cache_rule;

diff --git a/sim/igen/gen-idecode.c b/sim/igen/gen-idecode.c
index cb5ae54ece4a04631383915ae4ebd00d97320f8f..b24a2eb581fe321baa64ebf80b83f8afd1883999 100644 (file)
--- a/sim/igen/gen-idecode.c
+++ b/sim/igen/gen-idecode.c
@@ -750,7 +750,13 @@ print_idecode_validate (lf *file,
            /* Only need to validate constant (and reserved)
               bits. Skip any others */
            if (field->type != insn_field_int
-               && field->type != insn_field_reserved)
+               && field->type != insn_field_reserved
+               /* Consider a named field equal to a value to be just as
+                  constant as an integer field.  */
+               && (field->type != insn_field_string
+                   || field->conditions == NULL
+                   || field->conditions->test != insn_field_cond_eq
+                   || field->conditions->type != insn_field_cond_value))
              continue;
 
            /* Look through the list of opcode paths that lead to this

diff --git a/sim/igen/gen.c b/sim/igen/gen.c
index 5c1b4be52d09c215565bf37879da0c64fa2aa32b..9b7671172079353c5757164f35f1efeda80f8a4d 100644 (file)
--- a/sim/igen/gen.c
+++ b/sim/igen/gen.c
@@ -151,7 +151,9 @@ insn_field_cmp (insn_word_entry *l, insn_word_entry *r)
                return -1;
              /* The case of both fields having constant values should have
                 already have been handled because such fields are converted
-                into normal constant fields. */
+                into normal constant fields, but we must not make this
+                an assert, as we wouldn't gracefully handle an (invalid)
+                duplicate insn description.  */
              continue;
            }
          if (l->bit[bit_nr]->field->conditions->test == insn_field_cond_eq)
@@ -611,6 +613,18 @@ insns_bit_useless (insn_list *insns, decode_table *rule, int bit_nr)
                                    bit->field->val_string))
                /* a string field forced to constant? */
                is_useless = 0;
+             else if (bit->field->conditions != NULL
+                      && bit->field->conditions->test == insn_field_cond_eq
+                      && bit->field->conditions->type == insn_field_cond_value)
+               {
+                 int shift = bit->field->last - bit_nr;
+                 int bitvalue = (bit->field->conditions->value >> shift) & 1;
+
+                 if (value < 0)
+                   value = bitvalue;
+                 else if (value != bitvalue)
+                   is_useless = 0;
+               }
              else if (rule->search == decode_find_constants)
                /* the string field isn't constant */
                return 1;