place_gordian.c 4.89 KB
Newer Older
Alan Mishchenko committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
/*===================================================================*/
//  
//     place_gordian.c
//
//        Aaron P. Hurst, 2003-2007
//              ahurst@eecs.berkeley.edu
//
/*===================================================================*/

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <assert.h>
#include <limits.h>

#include "place_gordian.h"
#include "place_base.h"

19 20 21
ABC_NAMESPACE_IMPL_START


Alan Mishchenko committed
22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163

// --------------------------------------------------------------------
// Global variables
//
// --------------------------------------------------------------------

int g_place_numPartitions;


// --------------------------------------------------------------------
// globalPlace()
//
/// \brief Performs analytic placement using a GORDIAN-like algorithm.
//
/// Updates the positions of all non-fixed non-pad cells.
///
// --------------------------------------------------------------------
void globalPlace() {
  bool completionFlag = false;
  int iteration = 0;  

  printf("PLAC-10 : Global placement (wirelength-driven Gordian)\n");

  initPartitioning();

  // build matrices representing interconnections
  printf("QMAN-00 : \tconstructing initial quadratic problem...\n");
  constructQuadraticProblem();

  // iterate placement until termination condition is met
  while(!completionFlag) {
    printf("QMAN-01 : \titeration %d numPartitions = %d\n",iteration,g_place_numPartitions);
    
    // do the global optimization in each direction
    printf("QMAN-01 : \t\tglobal optimization\n");
    solveQuadraticProblem(!IGNORE_COG);
      
    // -------- PARTITIONING BASED CELL SPREADING ------

    // bisection
    printf("QMAN-01 : \t\tpartition refinement\n");
    if (REALLOCATE_PARTITIONS) reallocPartitions();
    completionFlag |= refinePartitions();
      
    printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
      
    iteration++;
  }
  
  // final global optimization
  printf("QMAN-02 : \t\tfinal pass\n");
  if (FINAL_REALLOCATE_PARTITIONS) reallocPartitions();
  solveQuadraticProblem(!IGNORE_COG);
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());

  // clean up
  sanitizePlacement();
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
  globalFixDensity(25, g_place_rowHeight*5);
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
}


// --------------------------------------------------------------------
// globalIncremental()
//
/// \brief Performs analytic placement using a GORDIAN-like algorithm.
//
/// Requires a valid set of partitions.
///
// --------------------------------------------------------------------

void   globalIncremental() {
  if (!g_place_rootPartition) {
    printf("WARNING: Can not perform incremental placement\n");
    globalPlace();
    return;
  }

  printf("PLAC-10 : Incremental global placement\n");

  incrementalPartition();

  printf("QMAN-00 : \tconstructing initial quadratic problem...\n");
  constructQuadraticProblem();

  solveQuadraticProblem(!IGNORE_COG);
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
  
  // clean up
  sanitizePlacement();
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
  globalFixDensity(25, g_place_rowHeight*5);
  printf("QMAN-01 : \t\twirelength = %e\n", getTotalWirelength());
}


// --------------------------------------------------------------------
// sanitizePlacement()
//
/// \brief Moves any cells that are outside of the core bounds to the nearest location within.
//
// --------------------------------------------------------------------
void sanitizePlacement() { 
  int c;
  float order_width = g_place_rowHeight;
  float x, y, edge, w, h;
  
  printf("QCLN-10 : \tsanitizing placement\n");

  for(c=0; c<g_place_numCells; c++) if (g_place_concreteCells[c]) {
    ConcreteCell *cell = g_place_concreteCells[c];
    if (cell->m_fixed || cell->m_parent->m_pad) {
      continue;
    }
    // the new locations of the cells will be distributed within
    // a small margin inside the border so that ordering is preserved
    order_width = g_place_rowHeight;

    x = cell->m_x, y = cell->m_y,
      w = cell->m_parent->m_width, h = cell->m_parent->m_height;

    if ((edge=x-w*0.5) < g_place_coreBounds.x) {
      x = g_place_coreBounds.x+w*0.5 +
        order_width/(1.0+g_place_coreBounds.x-edge);
    }
    else if ((edge=x+w*0.5) > g_place_coreBounds.x+g_place_coreBounds.w) {
      x = g_place_coreBounds.x+g_place_coreBounds.w-w*0.5 -
        order_width/(1.0+edge-g_place_coreBounds.x-g_place_coreBounds.w);
    }
    if ((edge=y-h*0.5) < g_place_coreBounds.y) {
      y = g_place_coreBounds.y+h*0.5 +
        order_width/(1.0+g_place_coreBounds.y-edge);
    }
    else if ((edge=y+h*0.5) > g_place_coreBounds.y+g_place_coreBounds.h) {
      y = g_place_coreBounds.y+g_place_coreBounds.h-h*0.5 -
        order_width/(1.0+edge-g_place_coreBounds.x-g_place_coreBounds.w);
    }
    cell->m_x = x;
    cell->m_y = y;
  }
}
164 165
ABC_NAMESPACE_IMPL_END