Subzero: Make liveness validation errors easier to interpret.

src/IceTargetLoweringARM32.cpp

 //===- subzero/src/IceTargetLoweringARM32.cpp - ARM32 lowering ------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 1040 matching lines @@
   Func->dump("After ARM32 codegen");
 
   // Register allocation. This requires instruction renumbering and full
   // liveness analysis.
   Func->renumberInstructions();
   if (Func->hasError())
     return;
   Func->liveness(Liveness_Intervals);
   if (Func->hasError())
     return;
+  // The post-codegen dump is done here, after liveness analysis and associated
+  // cleanup, to make the dump cleaner and more useful.
+  Func->dump("After initial ARM32 codegen");
   // Validate the live range computations. The expensive validation call is
   // deliberately only made when assertions are enabled.
   assert(Func->validateLiveness());
-  // The post-codegen dump is done here, after liveness analysis and associated
-  // cleanup, to make the dump cleaner and more useful.
-  Func->dump("After initial ARM32 codegen");
   Func->getVMetadata()->init(VMK_All);
   regAlloc(RAK_Global);
   if (Func->hasError())
     return;
 
   copyRegAllocFromInfWeightVariable64On32(Func->getVariables());
   Func->dump("After linear scan regalloc");
 
   if (getFlags().getEnablePhiEdgeSplit()) {
     Func->advancedPhiLowering();
@@ skipping 6069 matching lines @@
   // However, for compatibility with current NaCl LLVM, don't claim that.
   Str << ".eabi_attribute 14, 3   @ Tag_ABI_PCS_R9_use: Not used\n";
 }
 
 SmallBitVector TargetARM32::TypeToRegisterSet[RegARM32::RCARM32_NUM];
 SmallBitVector TargetARM32::TypeToRegisterSetUnfiltered[RegARM32::RCARM32_NUM];
 SmallBitVector TargetARM32::RegisterAliases[RegARM32::Reg_NUM];
 
 } // end of namespace ARM32
 } // end of namespace Ice