Emit banksel and movlp instructions.
Split large global data (both initialized and un-initialized) into multiple sections of <= 80 bytes.
Provide routines to manage PIC16 ABI naming conventions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71073 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PIC16/PIC16MemSelOpt.cpp b/lib/Target/PIC16/PIC16MemSelOpt.cpp
new file mode 100644
index 0000000..0458c5a
--- /dev/null
+++ b/lib/Target/PIC16/PIC16MemSelOpt.cpp
@@ -0,0 +1,163 @@
+//===-- PIC16MemSelOpt.cpp - PIC16 banksel optimizer --------------------===//
+//
+// 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 pass which optimizes the emitting of banksel
+// instructions before accessing data memory. This currently works within
+// a basic block only and keep tracks of the last accessed memory bank.
+// If memory access continues to be in the same bank it just makes banksel
+// immediate, which is a part of the insn accessing the data memory, from 1
+// to zero. The asm printer emits a banksel only if that immediate is 1.
+//
+// FIXME: this is not implemented yet. The banksel pass only works on local
+// basic blocks.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "pic16-codegen"
+#include "PIC16.h"
+#include "PIC16InstrInfo.h"
+#include "PIC16TargetAsmInfo.h"
+#include "PIC16TargetMachine.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/GlobalValue.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Support/Compiler.h"
+
+using namespace llvm;
+
+namespace {
+ struct VISIBILITY_HIDDEN MemSelOpt : public MachineFunctionPass {
+ static char ID;
+ MemSelOpt() : MachineFunctionPass(&ID) {}
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addPreservedID(MachineLoopInfoID);
+ AU.addPreservedID(MachineDominatorsID);
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+
+ virtual bool runOnMachineFunction(MachineFunction &MF);
+
+ virtual const char *getPassName() const {
+ return "PIC16 Memsel Optimizer";
+ }
+
+ bool processBasicBlock(MachineFunction &MF, MachineBasicBlock &MBB);
+ bool processInstruction(MachineInstr *MI);
+
+ private:
+ const TargetInstrInfo *TII; // Machine instruction info.
+ MachineBasicBlock *MBB; // Current basic block
+ std::string CurBank;
+
+ };
+ char MemSelOpt::ID = 0;
+}
+
+FunctionPass *llvm::createPIC16MemSelOptimizerPass() {
+ return new MemSelOpt();
+}
+
+
+/// runOnMachineFunction - Loop over all of the basic blocks, transforming FP
+/// register references into FP stack references.
+///
+bool MemSelOpt::runOnMachineFunction(MachineFunction &MF) {
+ TII = MF.getTarget().getInstrInfo();
+ bool Changed = false;
+ for (MachineFunction::iterator I = MF.begin(), E = MF.end();
+ I != E; ++I) {
+ Changed |= processBasicBlock(MF, *I);
+ }
+
+ return Changed;
+}
+
+/// processBasicBlock - Loop over all of the instructions in the basic block,
+/// transforming FP instructions into their stack form.
+///
+bool MemSelOpt::processBasicBlock(MachineFunction &MF, MachineBasicBlock &BB) {
+ bool Changed = false;
+ MBB = &BB;
+
+ // Let us assume that when entering a basic block now bank is selected.
+ // Ideally we should look at the predecessors for this information.
+ CurBank="";
+
+ for (MachineBasicBlock::iterator I = BB.begin(); I != BB.end(); ++I) {
+ Changed |= processInstruction(I);
+ }
+ return Changed;
+}
+
+bool MemSelOpt::processInstruction(MachineInstr *MI) {
+ bool Changed = false;
+
+ unsigned NumOperands = MI->getNumOperands();
+ // If this insn has only one operand, probably it is not going to
+ // access any data memory.
+ if (PIC16InstrInfo::hasNoMemOperand(*MI)) return Changed;
+
+ // Scan for the memory address operand.
+ // FIXME: Should we use standard interfaces like memoperands_iterator,
+ // hasMemOperand() etc ?
+ int MemOpPos = -1;
+ for (unsigned i = 0; i < NumOperands; i++) {
+ MachineOperand Op = MI->getOperand(i);
+ if (Op.getType() == MachineOperand::MO_GlobalAddress ||
+ Op.getType() == MachineOperand::MO_ExternalSymbol) {
+ // We found one mem operand. Next one should be BS.
+ MemOpPos = i;
+ break;
+ }
+ }
+
+ // If we did not find an insn accessing memory. Continue.
+ if (MemOpPos == -1) return Changed;
+
+ // Get the MemOp.
+ MachineOperand &Op = MI->getOperand(MemOpPos);
+
+ // If this is a pagesel material, handle it first.
+ if (MI->getOpcode() == PIC16::CALL) {
+ DebugLoc dl = MI->getDebugLoc();
+ BuildMI(*MBB, MI, dl, TII->get(PIC16::pagesel)).
+ addOperand(Op);
+ return true;
+ }
+
+ // Get the section name(NewBank) for MemOp.
+ std::string NewBank = CurBank;
+ if (Op.getType() == MachineOperand::MO_GlobalAddress &&
+ Op.getGlobal()->getType()->getAddressSpace() == PIC16ISD::RAM_SPACE) {
+ NewBank = Op.getGlobal()->getSection();
+ } else if (Op.getType() == MachineOperand::MO_ExternalSymbol) {
+ // External Symbol is generated for temp data and arguments. They are
+ // in fpdata.<functionname>.# section.
+ std::string Sym = Op.getSymbolName();
+ NewBank = getSectionNameForSym(Sym);
+ }
+
+ // If the previous and new section names are same, we don't need to
+ // emit banksel.
+ if (NewBank.compare(CurBank) != 0 ) {
+ DebugLoc dl = MI->getDebugLoc();
+ BuildMI(*MBB, MI, dl, TII->get(PIC16::banksel)).
+ addOperand(Op);
+ Changed = true;
+ CurBank = NewBank;
+ }
+
+ return Changed;
+}
+