Refactor VirtRegMap out of RegAllocLinearScan as the first part of bug

251 (providing a generic machine code rewriter/spiller).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11780 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/VirtRegMap.cpp

@@ -0,0 +1,55 @@
+//===-- llvm/CodeGen/VirtRegMap.cpp - Virtual Register Map ----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the virtual register map.
+//
+//===----------------------------------------------------------------------===//
+
+#include "VirtRegMap.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "Support/Statistic.h"
+#include <iostream>
+
+using namespace llvm;
+
+namespace {
+    Statistic<> numSpills("ra-linearscan", "Number of register spills");
+}
+
+int VirtRegMap::assignVirt2StackSlot(unsigned virtReg)
+{
+    assert(MRegisterInfo::isVirtualRegister(virtReg));
+    assert(v2ssMap_[toIndex(virtReg)] == NO_STACK_SLOT &&
+           "attempt to assign stack slot to already spilled register");
+    const TargetRegisterClass* rc =
+        mf_->getSSARegMap()->getRegClass(virtReg);
+    int frameIndex = mf_->getFrameInfo()->CreateStackObject(rc);
+    v2ssMap_[toIndex(virtReg)] = frameIndex;
+    ++numSpills;
+    return frameIndex;
+}
+
+std::ostream& llvm::operator<<(std::ostream& os, const VirtRegMap& vrm)
+{
+    const MRegisterInfo* mri = vrm.mf_->getTarget().getRegisterInfo();
+
+    std::cerr << "********** REGISTER MAP **********\n";
+    for (unsigned i = 0, e = vrm.v2pMap_.size(); i != e; ++i) {
+        if (vrm.v2pMap_[i] != VirtRegMap::NO_PHYS_REG)
+            std::cerr << "[reg" << VirtRegMap::fromIndex(i) << " -> "
+                      << mri->getName(vrm.v2pMap_[i]) << "]\n";
+    }
+    for (unsigned i = 0, e = vrm.v2ssMap_.size(); i != e; ++i) {
+        if (vrm.v2ssMap_[i] != VirtRegMap::NO_STACK_SLOT)
+            std::cerr << "[reg" << VirtRegMap::fromIndex(i) << " -> fi#"
+                      << vrm.v2ssMap_[i] << "]\n";
+    }
+    return std::cerr << '\n';
+}