1 files changed, 159 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Mips/MipsOs16.cpp b/contrib/llvm/lib/Target/Mips/MipsOs16.cpp
new file mode 100644
index 000000000000..ac4e55f8a1f5
--- /dev/null
+++ b/contrib/llvm/lib/Target/Mips/MipsOs16.cpp
@@ -0,0 +1,159 @@
+//===---- MipsOs16.cpp for Mips Option -Os16                       --------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines an optimization phase for the MIPS target.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Mips.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+#define DEBUG_TYPE "mips-os16"
+
+static cl::opt<std::string> Mips32FunctionMask(
+  "mips32-function-mask",
+  cl::init(""),
+  cl::desc("Force function to be mips32"),
+  cl::Hidden);
+
+namespace {
+  class MipsOs16 : public ModulePass {
+  public:
+    static char ID;
+
+    MipsOs16() : ModulePass(ID) {}
+
+    StringRef getPassName() const override { return "MIPS Os16 Optimization"; }
+
+    bool runOnModule(Module &M) override;
+  };
+
+  char MipsOs16::ID = 0;
+}
+
+// Figure out if we need float point based on the function signature.
+// We need to move variables in and/or out of floating point
+// registers because of the ABI
+//
+static  bool needsFPFromSig(Function &F) {
+  Type* RetType = F.getReturnType();
+  switch (RetType->getTypeID()) {
+  case Type::FloatTyID:
+  case Type::DoubleTyID:
+    return true;
+  default:
+    ;
+  }
+  if (F.arg_size() >=1) {
+    Argument &Arg = *F.arg_begin();
+    switch (Arg.getType()->getTypeID()) {
+    case Type::FloatTyID:
+    case Type::DoubleTyID:
+      return true;
+    default:
+      ;
+    }
+  }
+  return false;
+}
+
+// Figure out if the function will need floating point operations
+//
+static bool needsFP(Function &F) {
+  if (needsFPFromSig(F))
+    return true;
+  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
+    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
+         I != E; ++I) {
+      const Instruction &Inst = *I;
+      switch (Inst.getOpcode()) {
+      case Instruction::FAdd:
+      case Instruction::FSub:
+      case Instruction::FMul:
+      case Instruction::FDiv:
+      case Instruction::FRem:
+      case Instruction::FPToUI:
+      case Instruction::FPToSI:
+      case Instruction::UIToFP:
+      case Instruction::SIToFP:
+      case Instruction::FPTrunc:
+      case Instruction::FPExt:
+      case Instruction::FCmp:
+        return true;
+      default:
+        ;
+      }
+      if (const CallInst *CI = dyn_cast<CallInst>(I)) {
+        LLVM_DEBUG(dbgs() << "Working on call"
+                          << "\n");
+        Function &F_ =  *CI->getCalledFunction();
+        if (needsFPFromSig(F_))
+          return true;
+      }
+    }
+  return false;
+}
+
+
+bool MipsOs16::runOnModule(Module &M) {
+  bool usingMask = Mips32FunctionMask.length() > 0;
+  bool doneUsingMask = false; // this will make it stop repeating
+
+  LLVM_DEBUG(dbgs() << "Run on Module MipsOs16 \n"
+                    << Mips32FunctionMask << "\n");
+  if (usingMask)
+    LLVM_DEBUG(dbgs() << "using mask \n" << Mips32FunctionMask << "\n");
+
+  unsigned int functionIndex = 0;
+  bool modified = false;
+
+  for (auto &F : M) {
+    if (F.isDeclaration())
+      continue;
+
+    LLVM_DEBUG(dbgs() << "Working on " << F.getName() << "\n");
+    if (usingMask) {
+      if (!doneUsingMask) {
+        if (functionIndex == Mips32FunctionMask.length())
+          functionIndex = 0;
+        switch (Mips32FunctionMask[functionIndex]) {
+        case '1':
+          LLVM_DEBUG(dbgs() << "mask forced mips32: " << F.getName() << "\n");
+          F.addFnAttr("nomips16");
+          break;
+        case '.':
+          doneUsingMask = true;
+          break;
+        default:
+          break;
+        }
+        functionIndex++;
+      }
+    }
+    else {
+      if (needsFP(F)) {
+        LLVM_DEBUG(dbgs() << "os16 forced mips32: " << F.getName() << "\n");
+        F.addFnAttr("nomips16");
+      }
+      else {
+        LLVM_DEBUG(dbgs() << "os16 forced mips16: " << F.getName() << "\n");
+        F.addFnAttr("mips16");
+      }
+    }
+  }
+
+  return modified;
+}
+
+ModulePass *llvm::createMipsOs16Pass() { return new MipsOs16(); }