> 2005-06-02 Steven Bosscher <stevenb@suse.de>

[pf3gnuchains/gcc-fork.git] / gcc / params.def

diff --git a/gcc/params.def b/gcc/params.def
index 2dbc197..d9871a5 100644 (file)
--- a/gcc/params.def
+++ b/gcc/params.def
@@ -35,6 +35,14 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 
    Be sure to add an entry to invoke.texi summarizing the parameter.  */
 
+/* The maximum number of fields in a variable with only implicit uses
+   for which structure aliasing will consider trying to track each
+   field.  The default is 5.  */
+DEFPARAM (PARAM_SALIAS_MAX_IMPLICIT_FIELDS,
+         "salias-max-implicit-fields",
+         "The maximum number of fields in a structure variable without direct structure accesses that GCC will attempt to track separately",
+         5, 0, 0)
+   
 /* The maximum structure size at which the scalar replacement of
    aggregates (SRA) pass will perform block copies.  The default
    value, 0, implies that GCC will select the most appropriate size
@@ -364,6 +372,11 @@ DEFPARAM(PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND,
         "If number of candidates in the set is smaller, we always try to remove unused ivs during its optimization",
         10, 0, 0)
 
+DEFPARAM(PARAM_SCEV_MAX_EXPR_SIZE,
+        "scev-max-expr-size",
+        "Bound on size of expressions used in the scalar evolutions analyzer",
+        20, 0, 0)
+
 /* The product of the next two is used to decide whether or not to
    use .GLOBAL_VAR.  See tree-dfa.c.  */
 DEFPARAM(PARAM_GLOBAL_VAR_THRESHOLD,
@@ -430,6 +443,30 @@ DEFPARAM (PARAM_INTEGER_SHARE_LIMIT,
          "The upper bound for sharing integer constants",
          256, 2, 2)
 
+/* Incremental SSA updates for virtual operands may be very slow if
+   there is a large number of mappings to process.  In those cases, it
+   is faster to rewrite the virtual symbols from scratch as if they
+   had been recently introduced.  This heuristic cannot be applied to
+   SSA mappings for real SSA names, only symbols kept in FUD chains.
+
+   PARAM_MIN_VIRTUAL_MAPPINGS specifies the minimum number of virtual
+   mappings that should be registered to trigger the heuristic.
+   
+   PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO specifies the ratio between
+   mappings and symbols.  If the number of virtual mappings is
+   PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO bigger than the number of
+   virtual symbols to be updated, then the updater switches to a full
+   update for those symbols.  */
+DEFPARAM (PARAM_MIN_VIRTUAL_MAPPINGS,
+         "min-virtual-mappings",
+         "Minimum number of virtual mappings to consider switching to full virtual renames",
+         100, 0, 0)
+
+DEFPARAM (PARAM_VIRTUAL_MAPPINGS_TO_SYMS_RATIO,
+         "virtual-mappings-ratio",
+         "Ratio between virtual mappings and virtual symbols to do full virtual renames",
+         3, 0, 0)
+
 /*
 Local variables:
 mode:c