Baby steps towards ARM fast-isel.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109047 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/ARM/ARMFastISel.cpp

@@ -0,0 +1,71 @@
+//===-- ARMFastISel.cpp - ARM FastISel implementation ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the ARM-specific support for the FastISel class. Some
+// of the target-specific code is generated by tablegen in the file
+// ARMGenFastISel.inc, which is #included here.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARM.h"
+#include "ARMRegisterInfo.h"
+#include "ARMTargetMachine.h"
+#include "ARMSubtarget.h"
+#include "llvm/CallingConv.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/CodeGen/Analysis.h"
+#include "llvm/CodeGen/FastISel.h"
+#include "llvm/CodeGen/FunctionLoweringInfo.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Support/CallSite.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Target/TargetOptions.h"
+using namespace llvm;
+
+namespace {
+
+class ARMFastISel : public FastISel {
+
+  /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can
+  /// make the right decision when generating code for different targets.
+  const ARMSubtarget *Subtarget;
+
+  public:
+    explicit ARMFastISel(FunctionLoweringInfo &funcInfo) : FastISel(funcInfo) {
+      Subtarget = &TM.getSubtarget<ARMSubtarget>();
+    }
+
+    virtual bool TargetSelectInstruction(const Instruction *I);
+
+  #include "ARMGenFastISel.inc"
+
+  };
+
+} // end anonymous namespace
+
+// #include "ARMGenCallingConv.inc"
+
+bool ARMFastISel::TargetSelectInstruction(const Instruction *I) {
+  switch (I->getOpcode()) {
+    default: break;
+  }
+  return false;
+}
+
+namespace llvm {
+  llvm::FastISel *ARM::createFastISel(FunctionLoweringInfo &funcInfo) {
+    return new ARMFastISel(funcInfo);
+  }
+}

lib/Target/ARM/ARMISelLowering.cpp

@@ -694,6 +694,12 @@ TargetRegisterClass *ARMTargetLowering::getRegClassFor(EVT VT) const {
   return TargetLowering::getRegClassFor(VT);
 }
 
+// Create a fast isel object.
+FastISel *
+ARMTargetLowering::createFastISel(FunctionLoweringInfo &funcInfo) const {
+  return ARM::createFastISel(funcInfo);
+}
+
 /// getFunctionAlignment - Return the Log2 alignment of this function.
 unsigned ARMTargetLowering::getFunctionAlignment(const Function *F) const {
   return getTargetMachine().getSubtarget<ARMSubtarget>().isThumb() ? 1 : 2;

lib/Target/ARM/ARMISelLowering.h

@@ -17,6 +17,7 @@
 
 #include "ARMSubtarget.h"
 #include "llvm/Target/TargetLowering.h"
+#include "llvm/CodeGen/FastISel.h"
 #include "llvm/CodeGen/SelectionDAG.h"
 #include "llvm/CodeGen/CallingConvLower.h"
 #include <vector>
@@ -261,6 +262,10 @@ namespace llvm {
     /// getFunctionAlignment - Return the Log2 alignment of this function.
     virtual unsigned getFunctionAlignment(const Function *F) const;
 
+    /// createFastISel - This method returns a target specific FastISel object,
+    /// or null if the target does not support "fast" ISel.
+    virtual FastISel *createFastISel(FunctionLoweringInfo &funcInfo) const;
+
     Sched::Preference getSchedulingPreference(SDNode *N) const;
 
     bool isShuffleMaskLegal(const SmallVectorImpl<int> &M, EVT VT) const;
@@ -387,6 +392,10 @@ namespace llvm {
                                         unsigned BinOpcode) const;
 
   };
+  
+  namespace ARM {
+    FastISel *createFastISel(FunctionLoweringInfo &funcInfo);
+  }
 }
 
 #endif  // ARMISELLOWERING_H

lib/Target/ARM/CMakeLists.txt

@@ -11,6 +11,7 @@ tablegen(ARMGenDAGISel.inc -gen-dag-isel)
 tablegen(ARMGenCallingConv.inc -gen-callingconv)
 tablegen(ARMGenSubtarget.inc -gen-subtarget)
 tablegen(ARMGenEDInfo.inc -gen-enhanced-disassembly-info)
+tablegen(ARMFastISel.inc -gen-fast-isel)
 
 add_llvm_target(ARMCodeGen
   ARMAsmPrinter.cpp

lib/Target/ARM/Makefile

@@ -17,7 +17,8 @@ BUILT_SOURCES = ARMGenRegisterInfo.h.inc ARMGenRegisterNames.inc \
                 ARMGenInstrInfo.inc ARMGenAsmWriter.inc \
                 ARMGenDAGISel.inc ARMGenSubtarget.inc \
                 ARMGenCodeEmitter.inc ARMGenCallingConv.inc \
-                ARMGenDecoderTables.inc ARMGenEDInfo.inc
+                ARMGenDecoderTables.inc ARMGenEDInfo.inc \
+                ARMGenFastISel.inc
 
 DIRS = AsmPrinter AsmParser Disassembler TargetInfo
 

test/CodeGen/ARM/fast-isel.ll

@@ -0,0 +1,15 @@
+; RUN: llc < %s -fast-isel -fast-isel-abort -march=arm
+
+; Very basic fast-isel functionality.
+
+define i32 @add(i32 %a, i32 %b) nounwind ssp {
+entry:
+  %a.addr = alloca i32, align 4
+  %b.addr = alloca i32, align 4
+  store i32 %a, i32* %a.addr
+  store i32 %b, i32* %b.addr
+  %tmp = load i32* %a.addr
+  %tmp1 = load i32* %b.addr
+  %add = add nsw i32 %tmp, %tmp1
+  ret i32 %add
+}