8217716: Remove dead code in PhaseChaitin
authorredestad
Thu, 24 Jan 2019 14:43:56 +0100
changeset 53468 d927fc999582
parent 53467 97cf88608d76
child 53469 1d953ae4d39f
8217716: Remove dead code in PhaseChaitin Reviewed-by: thartmann
src/hotspot/share/libadt/vectset.hpp
src/hotspot/share/opto/chaitin.cpp
src/hotspot/share/opto/chaitin.hpp
src/hotspot/share/opto/ifg.cpp
--- a/src/hotspot/share/libadt/vectset.hpp	Thu Jan 24 12:32:42 2019 +0000
+++ b/src/hotspot/share/libadt/vectset.hpp	Thu Jan 24 14:43:56 2019 +0100
@@ -110,7 +110,6 @@
 
   // Expose internals for speed-critical fast iterators
   uint word_size() const { return size; }
-  uint32_t* EXPOSE() const { return data; }
 
   // Fast inlined "test and set".  Replaces the idiom:
   //     if( visited[idx] ) return;
--- a/src/hotspot/share/opto/chaitin.cpp	Thu Jan 24 12:32:42 2019 +0000
+++ b/src/hotspot/share/opto/chaitin.cpp	Thu Jan 24 14:43:56 2019 +0100
@@ -749,6 +749,17 @@
       LRG& lrg = lrgs(vreg);
       if (vreg) {              // No vreg means un-allocable (e.g. memory)
 
+        // Check for float-vs-int live range (used in register-pressure
+        // calculations)
+        const Type *n_type = n->bottom_type();
+        if (n_type->is_floatingpoint()) {
+          lrg._is_float = 1;
+        }
+
+#ifndef PRODUCT
+        // Collect bits not used by product code, but which may be useful for
+        // debugging.
+
         // Collect has-copy bit
         if (idx) {
           lrg._has_copy = 1;
@@ -757,13 +768,6 @@
           copy_src._has_copy = 1;
         }
 
-        // Check for float-vs-int live range (used in register-pressure
-        // calculations)
-        const Type *n_type = n->bottom_type();
-        if (n_type->is_floatingpoint()) {
-          lrg._is_float = 1;
-        }
-
         // Check for twice prior spilling.  Once prior spilling might have
         // spilled 'soft', 2nd prior spill should have spilled 'hard' and
         // further spilling is unlikely to make progress.
@@ -774,7 +778,6 @@
           }
         }
 
-#ifndef PRODUCT
         if (trace_spilling() && lrg._def != NULL) {
           // collect defs for MultiDef printing
           if (lrg._defs == NULL) {
@@ -1109,8 +1112,6 @@
 #endif
 }
 
-#define REGISTER_CONSTRAINED 16
-
 // Compute cost/area ratio, in case we spill.  Build the lo-degree list.
 void PhaseChaitin::cache_lrg_info( ) {
   Compile::TracePhase tp("chaitinCacheLRG", &timers[_t_chaitinCacheLRG]);
@@ -1145,56 +1146,6 @@
   }
 }
 
-// Simplify the IFG by removing LRGs of low degree that have NO copies
-void PhaseChaitin::Pre_Simplify( ) {
-
-  // Warm up the lo-degree no-copy list
-  int lo_no_copy = 0;
-  for (uint i = 1; i < _lrg_map.max_lrg_id(); i++) {
-    if ((lrgs(i).lo_degree() && !lrgs(i)._has_copy) ||
-        !lrgs(i).alive() ||
-        lrgs(i)._must_spill) {
-      lrgs(i)._next = lo_no_copy;
-      lo_no_copy = i;
-    }
-  }
-
-  while( lo_no_copy ) {
-    uint lo = lo_no_copy;
-    lo_no_copy = lrgs(lo)._next;
-    int size = lrgs(lo).num_regs();
-
-    // Put the simplified guy on the simplified list.
-    lrgs(lo)._next = _simplified;
-    _simplified = lo;
-
-    // Yank this guy from the IFG.
-    IndexSet *adj = _ifg->remove_node( lo );
-
-    // If any neighbors' degrees fall below their number of
-    // allowed registers, then put that neighbor on the low degree
-    // list.  Note that 'degree' can only fall and 'numregs' is
-    // unchanged by this action.  Thus the two are equal at most once,
-    // so LRGs hit the lo-degree worklists at most once.
-    IndexSetIterator elements(adj);
-    uint neighbor;
-    while ((neighbor = elements.next()) != 0) {
-      LRG *n = &lrgs(neighbor);
-      assert( _ifg->effective_degree(neighbor) == n->degree(), "" );
-
-      // Check for just becoming of-low-degree
-      if( n->just_lo_degree() && !n->_has_copy ) {
-        assert(!(*_ifg->_yanked)[neighbor],"Cannot move to lo degree twice");
-        // Put on lo-degree list
-        n->_next = lo_no_copy;
-        lo_no_copy = neighbor;
-      }
-    }
-  } // End of while lo-degree no_copy worklist not empty
-
-  // No more lo-degree no-copy live ranges to simplify
-}
-
 // Simplify the IFG by removing LRGs of low degree.
 void PhaseChaitin::Simplify( ) {
   Compile::TracePhase tp("chaitinSimplify", &timers[_t_chaitinSimplify]);
@@ -1616,18 +1567,6 @@
   return spill_reg-LRG::SPILL_REG;      // Return number of spills
 }
 
-// Copy 'was_spilled'-edness from the source Node to the dst Node.
-void PhaseChaitin::copy_was_spilled( Node *src, Node *dst ) {
-  if( _spilled_once.test(src->_idx) ) {
-    _spilled_once.set(dst->_idx);
-    lrgs(_lrg_map.find(dst))._was_spilled1 = 1;
-    if( _spilled_twice.test(src->_idx) ) {
-      _spilled_twice.set(dst->_idx);
-      lrgs(_lrg_map.find(dst))._was_spilled2 = 1;
-    }
-  }
-}
-
 // Set the 'spilled_once' or 'spilled_twice' flag on a node.
 void PhaseChaitin::set_was_spilled( Node *n ) {
   if( _spilled_once.test_set(n->_idx) )
--- a/src/hotspot/share/opto/chaitin.hpp	Thu Jan 24 12:32:42 2019 +0000
+++ b/src/hotspot/share/opto/chaitin.hpp	Thu Jan 24 14:43:56 2019 +0100
@@ -35,12 +35,11 @@
 #include "opto/regmask.hpp"
 #include "opto/machnode.hpp"
 
-class LoopTree;
 class Matcher;
 class PhaseCFG;
 class PhaseLive;
 class PhaseRegAlloc;
-class   PhaseChaitin;
+class PhaseChaitin;
 
 #define OPTO_DEBUG_SPLIT_FREQ  BLOCK_FREQUENCY(0.001)
 #define OPTO_LRG_HIGH_FREQ     BLOCK_FREQUENCY(0.25)
@@ -136,7 +135,6 @@
 
   void Insert( OptoReg::Name reg ) { _mask.Insert(reg);  debug_only(_msize_valid=0;) }
   void Remove( OptoReg::Name reg ) { _mask.Remove(reg);  debug_only(_msize_valid=0;) }
-  void clear_to_pairs() { _mask.clear_to_pairs(); debug_only(_msize_valid=0;) }
   void clear_to_sets()  { _mask.clear_to_sets(_num_regs); debug_only(_msize_valid=0;) }
 
   // Number of registers this live range uses when it colors
@@ -237,9 +235,6 @@
   // Add edge between a and b.  Returns true if actually addded.
   int add_edge( uint a, uint b );
 
-  // Add edge between a and everything in the vector
-  void add_vector( uint a, IndexSet *vec );
-
   // Test for edge existance
   int test_edge( uint a, uint b ) const;
 
@@ -401,7 +396,6 @@
 
   PhaseLive *_live;             // Liveness, used in the interference graph
   PhaseIFG *_ifg;               // Interference graph (for original chunk)
-  Node_List **_lrg_nodes;       // Array of node; lists for lrgs which spill
   VectorSet _spilled_once;      // Nodes that have been spilled
   VectorSet _spilled_twice;     // Nodes that have been spilled twice
 
@@ -496,8 +490,7 @@
   void de_ssa();
 
   // Add edge between reg and everything in the vector.
-  // Same as _ifg->add_vector(reg,live) EXCEPT use the RegMask
-  // information to trim the set of interferences.  Return the
+  // Use the RegMask information to trim the set of interferences.  Return the
   // count of edges added.
   void interfere_with_live(uint lid, IndexSet* liveout);
 #ifdef ASSERT
@@ -666,17 +659,9 @@
   // coalescing, it should Simplify.  This call sets the was-lo-degree bit.
   void set_was_low();
 
-  // Split live-ranges that must spill due to register conflicts (as opposed
-  // to capacity spills).  Typically these are things def'd in a register
-  // and used on the stack or vice-versa.
-  void pre_spill();
-
   // Init LRG caching of degree, numregs.  Init lo_degree list.
   void cache_lrg_info( );
 
-  // Simplify the IFG by removing LRGs of low degree with no copies
-  void Pre_Simplify();
-
   // Simplify the IFG by removing LRGs of low degree
   void Simplify();
 
@@ -692,8 +677,6 @@
   // Return new number of live ranges
   uint Split(uint maxlrg, ResourceArea* split_arena);
 
-  // Copy 'was_spilled'-edness from one Node to another.
-  void copy_was_spilled( Node *src, Node *dst );
   // Set the 'spilled_once' or 'spilled_twice' flag on a node.
   void set_was_spilled( Node *n );
 
--- a/src/hotspot/share/opto/ifg.cpp	Thu Jan 24 12:32:42 2019 +0000
+++ b/src/hotspot/share/opto/ifg.cpp	Thu Jan 24 14:43:56 2019 +0100
@@ -67,20 +67,6 @@
   return _adjs[a].insert( b );
 }
 
-// Add an edge between 'a' and everything in the vector.
-void PhaseIFG::add_vector( uint a, IndexSet *vec ) {
-  // IFG is triangular, so do the inserts where 'a' < 'b'.
-  assert( !_is_square, "only on triangular" );
-  IndexSet *adjs_a = &_adjs[a];
-  if( !vec->count() ) return;
-
-  IndexSetIterator elements(vec);
-  uint neighbor;
-  while ((neighbor = elements.next()) != 0) {
-    add_edge( a, neighbor );
-  }
-}
-
 // Is there an edge between a and b?
 int PhaseIFG::test_edge( uint a, uint b ) const {
   // Sort a and b, so that a is larger