Eliminate false DVs on parallel compares.

1 files changed, 57 insertions, 7 deletions

diff --git a/gas/config/tc-ia64.c b/gas/config/tc-ia64.c
index 7e0193d..25cdfcd 100644
--- a/gas/config/tc-ia64.c
+++ b/gas/config/tc-ia64.c
@@ -521,6 +521,7 @@ static struct rsrc {
   char *file;                       /* what file marked this dependency */
   int line;                         /* what line marked this dependency */
   struct mem_offset mem_offset;     /* optional memory offset hint */
+  enum { CMP_NONE, CMP_OR, CMP_AND } cmp_type; /* OR or AND compare? */
   int path;                         /* corresponding code entry index */
 } *regdeps = NULL;
 static int regdepslen = 0;
@@ -528,6 +529,7 @@ static int regdepstotlen = 0;
 static const char *dv_mode[] = { "RAW", "WAW", "WAR" };
 static const char *dv_sem[] = { "none", "implied", "impliedf",
 				"data", "instr", "specific", "other" };
+static const char *dv_cmp_type[] = { "none", "OR", "AND" };
 
 /* Current state of PR mutexation */
 static struct qpmutex {
@@ -6374,6 +6376,7 @@ specify_resource (dep, idesc, type, specs, note, path)
   tmpl.mem_offset.hint = 0;
   tmpl.specific = 1;
   tmpl.index = 0;
+  tmpl.cmp_type = CMP_NONE;
 
 #define UNHANDLED \
 as_warn (_("Unhandled dependency %s for %s (%s), note %d"), \
@@ -7008,11 +7011,16 @@ dep->name, idesc->name, (rsrc_write?"write":"read"), note)
 	    {
 	      int p1 = CURR_SLOT.opnd[0].X_add_number - REG_P;
 	      int p2 = CURR_SLOT.opnd[1].X_add_number - REG_P;
+	      int or_andcm = strstr(idesc->name, "or.andcm") != NULL;
+	      int and_orcm = strstr(idesc->name, "and.orcm") != NULL;
+
 	      if ((idesc->operands[0] == IA64_OPND_P1
 		   || idesc->operands[0] == IA64_OPND_P2)
 		  && p1 != 0 && p1 != 63)
 		{
 		  specs[count] = tmpl;
+		  specs[count].cmp_type = 
+		    (or_andcm ? CMP_OR : (and_orcm ? CMP_AND : CMP_NONE));
 		  specs[count++].index = p1;
 		}
 	      if ((idesc->operands[1] == IA64_OPND_P1
@@ -7020,6 +7028,8 @@ dep->name, idesc->name, (rsrc_write?"write":"read"), note)
 		  && p2 != 0 && p2 != 63)
 		{
 		  specs[count] = tmpl;
+		  specs[count].cmp_type = 
+		    (or_andcm ? CMP_AND : (and_orcm ? CMP_OR : CMP_NONE));
 		  specs[count++].index = p2;
 		}
 	    }
@@ -7462,13 +7472,27 @@ dep->name, idesc->name, (rsrc_write?"write":"read"), note)
 	{
 	  if (rsrc_write)
 	    {
-	      for (i = 0; i < idesc->num_outputs; i++)
-		if ((idesc->operands[i] == IA64_OPND_P1
-		     || idesc->operands[i] == IA64_OPND_P2)
-		    && CURR_SLOT.opnd[i].X_add_number - REG_P == 63)
-		  {
-		    specs[count++] = tmpl;
-		  }
+              int p1 = CURR_SLOT.opnd[0].X_add_number - REG_P;
+              int p2 = CURR_SLOT.opnd[1].X_add_number - REG_P;
+	      int or_andcm = strstr(idesc->name, "or.andcm") != NULL;
+	      int and_orcm = strstr(idesc->name, "and.orcm") != NULL;
+
+	      if (p1 == 63 
+		  && (idesc->operands[0] == IA64_OPND_P1
+		      || idesc->operands[0] == IA64_OPND_P2))
+		{
+                  specs[count] = tmpl;
+		  specs[count++].cmp_type = 
+		    (or_andcm ? CMP_OR : (and_orcm ? CMP_AND : CMP_NONE));
+		}
+	      if (p2 == 63
+		  && (idesc->operands[1] == IA64_OPND_P1
+		      || idesc->operands[1] == IA64_OPND_P2))
+		{
+                  specs[count] = tmpl;
+		  specs[count++].cmp_type = 
+		    (or_andcm ? CMP_AND : (and_orcm ? CMP_OR : CMP_NONE));
+		}
 	    }
 	  else
 	    {
@@ -7951,6 +7975,32 @@ resources_match (rs, idesc, note, qp_regno, path)
 	    }
 	}
 
+      /* Skip apparent PR write conflicts where both writes are an AND or both
+	 writes are an OR. */
+      if (rs->dependency->specifier == IA64_RS_PR
+	  || rs->dependency->specifier == IA64_RS_PR63)
+	{
+	  if (specs[count].cmp_type != CMP_NONE
+	      && specs[count].cmp_type == rs->cmp_type)
+	    {
+	      if (md.debug_dv)
+		fprintf (stderr, "  %s on parallel compare allowed (PR%d)\n",
+			 dv_mode[rs->dependency->mode],
+			 rs->dependency->specifier == IA64_RS_PR ?
+			 specs[count].index : 63);
+	      continue;
+	    }
+	  if (md.debug_dv)
+	    fprintf (stderr, 
+		     "  %s on parallel compare conflict %s vs %s on PR%d\n",
+		     dv_mode[rs->dependency->mode],
+		     dv_cmp_type[rs->cmp_type], 
+		     dv_cmp_type[specs[count].cmp_type],
+		     rs->dependency->specifier == IA64_RS_PR ?
+		     specs[count].index : 63);
+		     
+	}
+
       /* If either resource is not specific, conservatively assume a conflict
        */
       if (!specs[count].specific || !rs->specific)