//
// 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.
//
//===----------------------------------------------------------------------===//
//
//
//===---------------------------------------------------------------------===//
-#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"));
+
-FunctionPass *llvm::createRegisterAllocator() {
+//===---------------------------------------------------------------------===//
+///
+/// createRegisterAllocator - choose the appropriate register allocator.
+///
+//===---------------------------------------------------------------------===//
+FunctionPass *llvm::createRegisterAllocator(CodeGenOpt::Level OptLevel) {
RegisterRegAlloc::FunctionPassCtor Ctor = RegisterRegAlloc::getDefault();
-
+
if (!Ctor) {
- Ctor = RegisterRegAlloc::FindCtor(RegAlloc);
- assert(Ctor && "No register allocator found");
- if (!Ctor) Ctor = RegisterRegAlloc::FirstCtor();
- RegisterRegAlloc::setDefault(Ctor);
+ Ctor = RegAlloc;
+ RegisterRegAlloc::setDefault(RegAlloc);
+ }
+
+ // This forces linking of the linear scan register allocator,
+ // so -regalloc=linearscan still works in clang.
+ if (Ctor == createLinearScanRegisterAllocator)
+ return createLinearScanRegisterAllocator();
+
+ 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 createGreedyRegisterAllocator();
}
-
- assert(Ctor && "No register allocator found");
-
- return Ctor();
}