[llvm-commits] [llvm] r103170 - /llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp

[Evan Cheng]

Author: evancheng
Date: Thu May  6 01:23:31 2010
New Revision: 103170

URL: http://llvm.org/viewvc/llvm-project?rev=103170&view=rev
Log:
Fixes a coalescer bug that caused llc to crash on 2009-11-30-LiveVariablesBug.ll
with the fix in 103157.

%reg1039:1<def> = VMOVS %S1<kill>, pred:14, pred:%reg0
is not coalescable since none of the super-registers of S1 are in reg1039's
register class: DPR_VFP2. But it is still a legal copy instruction so it should
not assert.

Modified:
    llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp

Modified: llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp?rev=103170&r1=103169&r2=103170&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp (original)
+++ llvm/trunk/lib/CodeGen/SimpleRegisterCoalescing.cpp Thu May  6 01:23:31 2010
@@ -1255,7 +1255,12 @@
                                                unsigned &RealDstReg) {
   const TargetRegisterClass *RC = mri_->getRegClass(SrcReg);
   RealDstReg = tri_->getMatchingSuperReg(DstReg, SubIdx, RC);
-  assert(RealDstReg && "Invalid extract_subreg instruction!");
+  if (!RealDstReg) {
+    DEBUG(dbgs() << "\tIncompatible source regclass: "
+                 << "none of the super-registers of " << tri_->getName(DstReg)
+                 << " are in " << RC->getName() << ".\n");
+    return false;
+  }
 
   LiveInterval &RHS = li_->getInterval(SrcReg);
   // For this type of EXTRACT_SUBREG, conservatively
@@ -1293,7 +1298,12 @@
                                                unsigned &RealSrcReg) {
   const TargetRegisterClass *RC = mri_->getRegClass(DstReg);
   RealSrcReg = tri_->getMatchingSuperReg(SrcReg, SubIdx, RC);
-  assert(RealSrcReg && "Invalid extract_subreg instruction!");
+  if (!RealSrcReg) {
+    DEBUG(dbgs() << "\tIncompatible destination regclass: "
+                 << "none of the super-registers of " << tri_->getName(SrcReg)
+                 << " are in " << RC->getName() << ".\n");
+    return false;
+  }
 
   LiveInterval &LHS = li_->getInterval(DstReg);
   if (li_->hasInterval(RealSrcReg) &&
@@ -1419,7 +1429,8 @@
     assert(DstSubRC && "Illegal subregister index");
     if (!DstSubRC->contains(SrcSubReg)) {
       DEBUG(dbgs() << "\tIncompatible destination regclass: "
-                   << tri_->getName(SrcSubReg) << " not in "
+                   << "none of the super-registers of "
+                   << tri_->getName(SrcSubReg) << " are in "
                    << DstSubRC->getName() << ".\n");
       return false;             // Not coalescable.
     }
@@ -1436,7 +1447,8 @@
     assert(SrcSubRC && "Illegal subregister index");
     if (!SrcSubRC->contains(DstSubReg)) {
       DEBUG(dbgs() << "\tIncompatible source regclass: "
-                   << tri_->getName(DstSubReg) << " not in "
+                   << "none of the super-registers of "
+                   << tri_->getName(DstSubReg) << " are in "
                    << SrcSubRC->getName() << ".\n");
       (void)DstSubReg;
       return false;             // Not coalescable.