Subzero: Refactor x86 register representation to actively use aliases.

src/IceCfg.cpp

 //===- subzero/src/IceCfg.cpp - Control flow graph implementation ---------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 439 matching lines @@
   TimerMarker T(TimerStack::TT_doArgLowering, this);
   getTarget()->lowerArguments();
 }
 
 void Cfg::sortAllocas(CfgVector<Inst *> &Allocas, InstList &Insts,
                       bool IsKnownFrameOffset) {
   if (Allocas.empty())
     return;
   // Sort by decreasing alignment.  This does not really matter at the moment,
   // but will allow compacting stack allocation when we fuse to one alloca.
-  std::sort(Allocas.begin(), Allocas.end(),
-            [](Inst *I1, Inst *I2) {
-              auto *A1 = llvm::dyn_cast<InstAlloca>(I1);
-              auto *A2 = llvm::dyn_cast<InstAlloca>(I2);
-              return A1->getAlignInBytes() > A2->getAlignInBytes();
-            });
-  for (Inst *Instr: Allocas) {
+  std::sort(Allocas.begin(), Allocas.end(), [](Inst *I1, Inst *I2) {
+    auto *A1 = llvm::dyn_cast<InstAlloca>(I1);
+    auto *A2 = llvm::dyn_cast<InstAlloca>(I2);
+    return A1->getAlignInBytes() > A2->getAlignInBytes();
+  });
+  for (Inst *Instr : Allocas) {
     auto *Alloca = llvm::cast<InstAlloca>(Instr);
     // Move the alloca to its sorted position.
-    InstAlloca *NewAlloca = InstAlloca::create(this,
-                                               Alloca->getSizeInBytes(),
-                                               Alloca->getAlignInBytes(),
-                                               Alloca->getDest());
+    InstAlloca *NewAlloca =
+        InstAlloca::create(this, Alloca->getSizeInBytes(),
+                           Alloca->getAlignInBytes(), Alloca->getDest());
     if (IsKnownFrameOffset)
       NewAlloca->setKnownFrameOffset();
     Insts.push_front(NewAlloca);
     Alloca->setDeleted();
   }
 }
 
 void Cfg::processAllocas() {
   const uint32_t StackAlignment = getTarget()->getStackAlignment();
   CfgNode *EntryNode = getEntryNode();
@@ skipping 16 matching lines @@
       }
       uint32_t AlignmentParam = Alloca->getAlignInBytes();
       // For default align=0, set it to the real value 1, to avoid any
       // bit-manipulation problems below.
       AlignmentParam = std::max(AlignmentParam, 1u);
       assert(llvm::isPowerOf2_32(AlignmentParam));
       if (AlignmentParam > StackAlignment) {
         // Allocations aligned more than the stack require a frame pointer.
         RequiresFramePointer = true;
         AlignedAllocas.push_back(Alloca);
-      }
-      else
+      } else
         FixedAllocas.push_back(Alloca);
     }
   }
   // Look for alloca instructions in other blocks
   for (CfgNode *Node : Nodes) {
     if (Node == EntryNode)
       continue;
     for (Inst &Instr : Node->getInsts()) {
       if (llvm::isa<InstAlloca>(&Instr)) {
         // Allocations outside the entry block require a frame pointer.
@@ skipping 377 matching lines @@
     }
   }
   // Print each basic block
   for (CfgNode *Node : Nodes)
     Node->dump(this);
   if (isVerbose(IceV_Instructions))
     Str << "}\n";
 }
 
 } // end of namespace Ice