Rebased PNaCl localmods in LLVM to 223109

lib/Analysis/NaCl/PNaClABITypeChecker.cpp

+//===- PNaClABITypeChecker.cpp - Verify PNaCl ABI rules -------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Common type-checking code for module and function-level passes
+//
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/NaCl/PNaClABITypeChecker.h"
+#include "llvm/IR/Constant.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Metadata.h"
+
+using namespace llvm;
+
+bool PNaClABITypeChecker::isValidParamType(const Type *Ty) {
+  if (!(isValidScalarType(Ty) || isValidVectorType(Ty)))
+    return false;
+  if (const IntegerType *IntTy = dyn_cast<IntegerType>(Ty)) {
+    // PNaCl requires function arguments and return values to be 32
+    // bits or larger.  This avoids exposing architecture
+    // ABI-dependent differences about whether arguments or return
+    // values are zero-extended when calling a function with the wrong
+    // prototype.
+    if (IntTy->getBitWidth() < 32)
+      return false;
+  }
+  return true;
+}
+
+bool PNaClABITypeChecker::isValidFunctionType(const FunctionType *FTy) {
+  if (FTy->isVarArg())
+    return false;
+  if (!isValidParamType(FTy->getReturnType()))
+    return false;
+  for (unsigned I = 0, E = FTy->getNumParams(); I < E; ++I) {
+    if (!isValidParamType(FTy->getParamType(I)))
+      return false;
+  }
+  return true;
+}
+
+namespace {
+static inline bool NaClIsValidIntType(const Type *Ty) {
+  unsigned Width = cast<const IntegerType>(Ty)->getBitWidth();
+  return Width == 1 || Width == 8 || Width == 16 ||
+      Width == 32 || Width == 64;
+}
+}
+
+bool PNaClABITypeChecker::isValidScalarType(const Type *Ty) {
+  switch (Ty->getTypeID()) {
+    case Type::IntegerTyID: {
+      return NaClIsValidIntType(Ty);
+    }
+    case Type::VoidTyID:
+    case Type::FloatTyID:
+    case Type::DoubleTyID:
+      return true;
+    default:
+      return false;
+  }
+}
+
+// TODO(jfb) Handle 64-bit int and double, and 2xi1.
+bool PNaClABITypeChecker::isValidVectorType(const Type *Ty) {
+  if (!Ty->isVectorTy())
+    return false;
+  unsigned Elems = Ty->getVectorNumElements();
+  const Type *VTy = Ty->getVectorElementType();
+
+  switch (VTy->getTypeID()) {
+  case Type::IntegerTyID: {
+    unsigned Width = cast<const IntegerType>(VTy)->getBitWidth();
+    switch (Width) {
+    case 1: return Elems == 4 || Elems == 8 || Elems == 16;
+    case 8: return Elems == 16;
+    case 16: return Elems == 8;
+    case 32: return Elems == 4;
+    default: return false;
+    }
+  }
+  case Type::FloatTyID:
+    return Elems == 4;
+  default:
+    return false;
+  }
+}
+
+namespace {
+static inline bool NaClIsValidIntArithmeticType(const Type *Ty) {
+  return Ty->isIntegerTy() && !Ty->isIntegerTy(1)
+      && NaClIsValidIntType(Ty);
+}
+
+}
+
+bool PNaClABITypeChecker::isValidIntArithmeticType(const Type *Ty) {
+  if (isValidVectorType(Ty))
+    return NaClIsValidIntArithmeticType(Ty->getVectorElementType());
+  return NaClIsValidIntArithmeticType(Ty);
+}