X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FRegAllocLinearScan.cpp;h=30c602da3b1247e572ac9fa4814217011688854d;hb=7a01e959156ba4e0a15b45a1f153f67d1646c0a5;hp=f7f5dc74b5d3d38663b91e3ef97c8fbd3fc5bb05;hpb=857c4e01f85601cf2084adb860616256ee47c177;p=oota-llvm.git

diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp
index f7f5dc74b5d..30c602da3b1 100644
--- a/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/lib/CodeGen/RegAllocLinearScan.cpp
@@ -34,7 +34,10 @@
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/Compiler.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
 #include <algorithm>
 #include <set>
 #include <queue>
@@ -235,7 +238,7 @@ namespace {
         }
       }
       if (Error)
-        abort();
+        llvm_unreachable(0);
 #endif
       regUse_.clear();
       regUseBackUp_.clear();
@@ -482,7 +485,8 @@ void RALinScan::linearScan()
 {
   // linear scan algorithm
   DOUT << "********** LINEAR SCAN **********\n";
-  DOUT << "********** Function: " << mf_->getFunction()->getName() << '\n';
+  DEBUG(errs() << "********** Function: " 
+        << mf_->getFunction()->getName() << '\n');
 
   DEBUG(printIntervals("fixed", fixed_.begin(), fixed_.end()));
 
@@ -545,26 +549,6 @@ void RALinScan::linearScan()
     if (!isPhys && vrm_->getPreSplitReg(cur.reg))
       continue;
 
-    // A register defined by an implicit_def can be liveout the def BB and livein
-    // to a use BB. Add it to the livein set of the use BB's.
-    if (!isPhys && cur.empty()) {
-      if (MachineInstr *DefMI = mri_->getVRegDef(cur.reg)) {
-        assert(DefMI->getOpcode() == TargetInstrInfo::IMPLICIT_DEF);
-        MachineBasicBlock *DefMBB = DefMI->getParent();
-        SmallPtrSet<MachineBasicBlock*, 4> Seen;
-        Seen.insert(DefMBB);
-        for (MachineRegisterInfo::reg_iterator ri = mri_->reg_begin(cur.reg),
-               re = mri_->reg_end(); ri != re; ++ri) {
-          MachineInstr *UseMI = &*ri;
-          MachineBasicBlock *UseMBB = UseMI->getParent();
-          if (Seen.insert(UseMBB)) {
-            assert(TargetRegisterInfo::isPhysicalRegister(Reg) &&
-                   "Adding a virtual register to livein set?");
-            UseMBB->addLiveIn(Reg);
-          }
-        }
-      }
-    }
     for (LiveInterval::Ranges::const_iterator I = cur.begin(), E = cur.end();
          I != E; ++I) {
       const LiveRange &LR = *I;
@@ -1122,8 +1106,7 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur)
         DowngradedRegs.clear();
         assignRegOrStackSlotAtInterval(cur);
       } else {
-        cerr << "Ran out of registers during register allocation!\n";
-        exit(1);
+        llvm_report_error("Ran out of registers during register allocation!");
       }
       return;
     }
@@ -1226,7 +1209,6 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur)
   // mark our rollback point.
   std::vector<LiveInterval*> added;
   while (!spillIs.empty()) {
-    bool epicFail = false;
     LiveInterval *sli = spillIs.back();
     spillIs.pop_back();
     DOUT << "\t\t\tspilling(a): " << *sli << '\n';
@@ -1243,10 +1225,6 @@ void RALinScan::assignRegOrStackSlotAtInterval(LiveInterval* cur)
     addStackInterval(sli, ls_, li_, mri_, *vrm_);
     std::copy(newIs.begin(), newIs.end(), std::back_inserter(added));
     spilled.insert(sli->reg);
-
-    if (epicFail) {
-      //abort();
-    }
   }
 
   unsigned earliestStart = earliestStartInterval->beginNumber();
@@ -1356,9 +1334,15 @@ unsigned RALinScan::getFreePhysReg(LiveInterval* cur,
   unsigned FreeReg = 0;
   unsigned FreeRegInactiveCount = 0;
 
+  std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(cur->reg);
+  // Resolve second part of the hint (if possible) given the current allocation.
+  unsigned physReg = Hint.second;
+  if (physReg &&
+      TargetRegisterInfo::isVirtualRegister(physReg) && vrm_->hasPhys(physReg))
+    physReg = vrm_->getPhys(physReg);
+
   TargetRegisterClass::iterator I, E;
-  tie(I, E) = tri_->getAllocationOrder(RC,
-                                    mri_->getRegAllocationHint(cur->reg), *mf_);
+  tie(I, E) = tri_->getAllocationOrder(RC, Hint.first, physReg, *mf_);
   assert(I != E && "No allocatable register in this register class!");
 
   // Scan for the first available register.