Implements include/exclude register lists for translation.

src/IceTargetLowering.cpp

 //===- subzero/src/IceTargetLowering.cpp - Basic lowering implementation --===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 21 matching lines @@
 // (TargetLowering, TargetDataLowering, and TargetHeaderLowering) we use the
 // following named constructors. For reference, each target Foo needs to
 // implement the following named constructors and initializer:
 //
 // namespace Foo {
 //   unique_ptr<Ice::TargetLowering> createTargetLowering(Ice::Cfg *);
 //   unique_ptr<Ice::TargetDataLowering>
 //       createTargetDataLowering(Ice::GlobalContext*);
 //   unique_ptr<Ice::TargetHeaderLowering>
 //       createTargetHeaderLowering(Ice::GlobalContext *);
-//   void staticInit(const ::Ice::ClFlags &Flags);
+//   void staticInit(::Ice::GlobalContext *);
 // }
 #define SUBZERO_TARGET(X)                                                      \
   namespace X {                                                                \
   std::unique_ptr<::Ice::TargetLowering>                                       \
   createTargetLowering(::Ice::Cfg *Func);                                      \
   std::unique_ptr<::Ice::TargetDataLowering>                                   \
   createTargetDataLowering(::Ice::GlobalContext *Ctx);                         \
   std::unique_ptr<::Ice::TargetHeaderLowering>                                 \
   createTargetHeaderLowering(::Ice::GlobalContext *Ctx);                       \
-  void staticInit(const ::Ice::ClFlags &Flags);                                \
+  void staticInit(::Ice::GlobalContext *Ctx);                                  \
   } // end of namespace X
 #include "llvm/Config/SZTargets.def"
 #undef SUBZERO_TARGET
 
 namespace Ice {
 void LoweringContext::init(CfgNode *N) {
   Node = N;
   End = getNode()->getInsts().end();
   rewind();
   advanceForward(Next);
@@ skipping 46 matching lines @@
   LastSrc = llvm::cast<Variable>(Instr->getSrc(0));
 }
 
 Variable *LoweringContext::availabilityGet(Operand *Src) const {
   assert(Src);
   if (Src == LastDest)
     return LastSrc;
   return nullptr;
 }
 
+llvm::SmallBitVector TargetLowering::getRegisterSetMask(
+    GlobalContext *Ctx, SizeT NumRegs, SizeT NumRegClasses,
+    std::function<SizeT(int32_t)> RegClassFcn,
+    std::function<IceString(int32_t)> RegNameFcn) {
+  llvm::SmallBitVector RegMask(NumRegs);
+
+  // Collect registers to use.
+  const std::unordered_set<std::string> &RegUses =
+      Ctx->getFlags().getUseRestrictedRegisters();
+  std::vector<llvm::SmallBitVector> AllRegClass(NumRegClasses, RegMask);
+  std::vector<llvm::SmallBitVector> UseRegClass(NumRegClasses, RegMask);
+  for (SizeT i = 0; i < NumRegs; ++i) {
+    SizeT ClassIndex = RegClassFcn(i);

[Jim Stichnoth, 2016/01/13 16:24:54]

RegClassFcn is supposed to take an int32_t argument, but i is SizeT.

Maybe types would all work out if i and NumRegs were int32_t?

[Karl, 2016/01/14 18:27:19]

Done.

+    assert(ClassIndex < NumRegClasses);
+    AllRegClass[ClassIndex][i] = true;
+    if (RegUses.count(RegNameFcn(i)))
+      UseRegClass[ClassIndex][i] = true;
+  }
+  for (SizeT ClassIndex = 0; ClassIndex < NumRegClasses; ++ClassIndex) {
+    RegMask |= (UseRegClass[ClassIndex].any() ? UseRegClass[ClassIndex]
+                                              : AllRegClass[ClassIndex]);
+  }
+
+  // Remove registers to exclude.
+  const std::unordered_set<std::string> &RegExcludes =
+      Ctx->getFlags().getExcludedRegisters();
+  for (SizeT i = 0; i < NumRegs; ++i) {
+    if (RegExcludes.count(RegNameFcn(i)))
+      RegMask[i] = false;
+  }
+
+  // Trace registers available if requested.
+  if (BuildDefs::dump() && NumRegs &&
+      (Ctx->getFlags().getVerbose() & IceV_AvailableRegs)) {
+    Ostream &Out = Ctx->getStrEmit();

[Jim Stichnoth, 2016/01/13 16:24:54]

getStrDump()

and usually, the variable is named "Str".
i.e.:
  Ostream &Str = Ctx->getStrDump();

[Karl, 2016/01/14 18:27:19]

Done.

+    Out << "Registers available for register allocation:\n";
+    constexpr SizeT RegistersPerLine = 15;
+    bool AtBeginning = true;
+    SizeT Count = 0;
+    for (SizeT i = 0; i < NumRegs; ++i) {
+      if (!RegMask[i])
+        continue;
+      if (AtBeginning) {
+        Out << "  ";
+        AtBeginning = false;
+      } else {
+        Out << ", ";
+      }
+      if ((Count > 0) && ((Count % RegistersPerLine) == 0)) {
+        Out << "\n  ";
+      }
+      ++Count;
+      Out << RegNameFcn(i);
+    }
+    if (!AtBeginning)
+      Out << "\n";
+  }
+
+  return RegMask;
+}
+
 std::unique_ptr<TargetLowering>
 TargetLowering::createLowering(TargetArch Target, Cfg *Func) {
   switch (Target) {
   default:
     llvm::report_fatal_error("Unsupported target");
 #define SUBZERO_TARGET(X)                                                      \
   case Target_##X:                                                             \
     return ::X::createTargetLowering(Func);
 #include "llvm/Config/SZTargets.def"
 #undef SUBZERO_TARGET
   }
 }
 
-void TargetLowering::staticInit(const ClFlags &Flags) {
-  const TargetArch Target = Flags.getTargetArch();
+void TargetLowering::staticInit(GlobalContext *Ctx) {
+  const TargetArch Target = Ctx->getFlags().getTargetArch();
   // Call the specified target's static initializer.
   switch (Target) {
   default:
     llvm::report_fatal_error("Unsupported target");
 #define SUBZERO_TARGET(X)                                                      \
   case Target_##X: {                                                           \
     static bool InitGuard##X = false;                                          \
     if (InitGuard##X) {                                                        \
       return;                                                                  \
     }                                                                          \
     InitGuard##X = true;                                                       \
-    ::X::staticInit(Flags);                                                    \
+    ::X::staticInit(Ctx);                                                      \
   } break;
 #include "llvm/Config/SZTargets.def"
 #undef SUBZERO_TARGET
   }
 }
 
 TargetLowering::TargetLowering(Cfg *Func)
     : Func(Func), Ctx(Func->getContext()), Context() {}
 
 void TargetLowering::genTargetHelperCalls() {
@@ skipping 526 matching lines @@
   case Target_##X:                                                             \
     return ::X::createTargetHeaderLowering(Ctx);
 #include "llvm/Config/SZTargets.def"
 #undef SUBZERO_TARGET
   }
 }
 
 TargetHeaderLowering::~TargetHeaderLowering() = default;
 
 } // end of namespace Ice