Stub out a new LiveDebugVariables pass.

[oota-llvm.git] / lib / CodeGen / Passes.cpp

diff --git a/lib/CodeGen/Passes.cpp b/lib/CodeGen/Passes.cpp
index 04f390a2f842856566c1d3291fb16c3fa43370b4..3489db2e9f4f966a401ff9c7ac1ccbf1e58b2f62 100644 (file)
--- a/lib/CodeGen/Passes.cpp
+++ b/lib/CodeGen/Passes.cpp
@@ -2,8 +2,8 @@
 //
 //                     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 is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -12,31 +12,57 @@
 //
 //===---------------------------------------------------------------------===//
 
-#include "llvm/CodeGen/MachinePassRegistry.h"
+#include "llvm/CodeGen/RegAllocRegistry.h"
 #include "llvm/CodeGen/Passes.h"
-#include "llvm/Support/CommandLine.h"
-#include <iostream>
 
 using namespace llvm;
 
-namespace {
-  cl::opt<const char *, false, RegisterPassParser<RegisterRegAlloc> >
-  RegAlloc("regalloc",
-           cl::init("linearscan"),
-           cl::desc("Register allocator to use: (default = linearscan)")); 
-}
+//===---------------------------------------------------------------------===//
+///
+/// RegisterRegAlloc class - Track the registration of register allocators.
+///
+//===---------------------------------------------------------------------===//
+MachinePassRegistry RegisterRegAlloc::Registry;
+
+static FunctionPass *createDefaultRegisterAllocator() { return 0; }
+static RegisterRegAlloc
+defaultRegAlloc("default",
+                "pick register allocator based on -O option",
+                createDefaultRegisterAllocator);
+
+//===---------------------------------------------------------------------===//
+///
+/// RegAlloc command line options.
+///
+//===---------------------------------------------------------------------===//
+static cl::opt<RegisterRegAlloc::FunctionPassCtor, false,
+               RegisterPassParser<RegisterRegAlloc> >
+RegAlloc("regalloc",
+         cl::init(&createDefaultRegisterAllocator),
+         cl::desc("Register allocator to use"));
+
+
+//===---------------------------------------------------------------------===//
+///
+/// createRegisterAllocator - choose the appropriate register allocator.
+///
+//===---------------------------------------------------------------------===//
+FunctionPass *llvm::createRegisterAllocator(CodeGenOpt::Level OptLevel) {
+  RegisterRegAlloc::FunctionPassCtor Ctor = RegisterRegAlloc::getDefault();
 
-FunctionPass *llvm::createRegisterAllocator() {
-  RegisterRegAlloc::FunctionPassCtor Ctor = RegisterRegAlloc::getCache();
-  
   if (!Ctor) {
-    Ctor = RegisterRegAlloc::FindCtor(RegAlloc);
-    assert(Ctor && "No register allocator found");
-    if (!Ctor) Ctor = RegisterRegAlloc::FirstCtor();
-    RegisterRegAlloc::setCache(Ctor);
+    Ctor = RegAlloc;
+    RegisterRegAlloc::setDefault(RegAlloc);
+  }
+
+  if (Ctor != createDefaultRegisterAllocator)
+    return Ctor();
+
+  // When the 'default' allocator is requested, pick one based on OptLevel.
+  switch (OptLevel) {
+  case CodeGenOpt::None:
+    return createFastRegisterAllocator();
+  default:
+    return createLinearScanRegisterAllocator();
   }
-  
-  assert(Ctor && "No register allocator found");
-  
-  return Ctor();
 }