Add bswap intrinsics as documented in the Language Reference

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25309 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 55 insertions, 1 deletions

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 86cc564..71bcbd2 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -708,7 +708,8 @@ namespace {
 static const char *DoesntAccessMemoryTable[] = {
   // LLVM intrinsics:
   "llvm.frameaddress", "llvm.returnaddress", "llvm.readport",
-  "llvm.isunordered", "llvm.sqrt", "llvm.ctpop", "llvm.ctlz", "llvm.cttz",
+  "llvm.isunordered", "llvm.sqrt", "llvm.bswap.i16", "llvm.bswap.i32",
+  "llvm.bswap.i64", "llvm.ctpop", "llvm.ctlz", "llvm.cttz",
 
   "abs", "labs", "llabs", "imaxabs", "fabs", "fabsf", "fabsl",
   "trunc", "truncf", "truncl", "ldexp",
diff --git a/lib/Analysis/ConstantFolding.cpp b/lib/Analysis/ConstantFolding.cpp
index 4022bdd..915a7cb 100644
--- a/lib/Analysis/ConstantFolding.cpp
+++ b/lib/Analysis/ConstantFolding.cpp
@@ -37,6 +37,13 @@ llvm::canConstantFoldCallTo(Function *F) {
   switch (F->getIntrinsicID()) {
   case Intrinsic::isunordered:
   case Intrinsic::sqrt:
+  case Intrinsic::bswap_i16:
+  case Intrinsic::bswap_i32:
+  case Intrinsic::bswap_i64:
+  // FIXME: these should be constant folded as well
+  //case Intrinsic::ctpop:
+  //case Intrinsic::ctlz:
+  //case Intrinsic::cttz:
     return true;
   default: break;
   }
@@ -142,6 +149,14 @@ llvm::ConstantFoldCall(Function *F, const std::vector<Constant*> &Operands) {
         default:
           break;
       }
+    } else if (ConstantUInt *Op = dyn_cast<ConstantUInt>(Operands[0])) {
+      uint64_t V = Op->getValue();
+      if (Name == "llvm.bswap.i16")
+        return ConstantUInt::get(Ty, ByteSwap_16(V));
+      else if (Name == "llvm.bswap.i32")
+        return ConstantUInt::get(Ty, ByteSwap_32(V));
+      else if (Name == "llvm.bswap.i64")
+        return ConstantUInt::get(Ty, ByteSwap_64(V));
     }
   } else if (Operands.size() == 2) {
     if (ConstantFP *Op1 = dyn_cast<ConstantFP>(Operands[0])) {
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index 4e3b3e9..c4b69a4 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -298,6 +298,9 @@ bool llvm::isInstructionTriviallyDead(Instruction *I) {
       case Intrinsic::frameaddress:
       case Intrinsic::stacksave:
       case Intrinsic::isunordered:
+      case Intrinsic::bswap_i16:
+      case Intrinsic::bswap_i32:
+      case Intrinsic::bswap_i64:
       case Intrinsic::ctpop:
       case Intrinsic::ctlz:
       case Intrinsic::cttz:
diff --git a/lib/VMCore/Function.cpp b/lib/VMCore/Function.cpp
index 0cbe14c..3abfef9 100644
--- a/lib/VMCore/Function.cpp
+++ b/lib/VMCore/Function.cpp
@@ -207,6 +207,11 @@ unsigned Function::getIntrinsicID() const {
   assert(getName().size() != 5 && "'llvm.' is an invalid intrinsic name!");
 
   switch (getName()[5]) {
+  case 'b':
+    if (getName() == "llvm.bswap.i16") return Intrinsic::bswap_i16;
+    if (getName() == "llvm.bswap.i32") return Intrinsic::bswap_i32;
+    if (getName() == "llvm.bswap.i64") return Intrinsic::bswap_i64;
+    break;
   case 'c':
     if (getName() == "llvm.ctpop") return Intrinsic::ctpop;
     if (getName() == "llvm.cttz") return Intrinsic::cttz;
diff --git a/lib/VMCore/Verifier.cpp b/lib/VMCore/Verifier.cpp
index 9dd7184..f67a497 100644
--- a/lib/VMCore/Verifier.cpp
+++ b/lib/VMCore/Verifier.cpp
@@ -749,6 +749,36 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
     NumArgs = 0;
     break;
 
+  case Intrinsic::bswap_i16:
+    Assert1(FT->getNumParams() == 1,
+            "Illegal # arguments for intrinsic function!", IF);
+    Assert1(FT->getReturnType() == FT->getParamType(0),
+            "Return type does not match source type", IF);
+    Assert1(FT->getReturnType() == Type::UShortTy,
+            "Return type is not ushort!", IF);
+    NumArgs = 1;
+    break;    
+
+  case Intrinsic::bswap_i32:
+    Assert1(FT->getNumParams() == 1,
+            "Illegal # arguments for intrinsic function!", IF);
+    Assert1(FT->getReturnType() == FT->getParamType(0),
+            "Return type does not match source type", IF);
+    Assert1(FT->getReturnType() == Type::UIntTy,
+            "Return type is not uint!", IF);
+    NumArgs = 1;
+    break;    
+
+  case Intrinsic::bswap_i64:
+    Assert1(FT->getNumParams() == 1,
+            "Illegal # arguments for intrinsic function!", IF);
+    Assert1(FT->getReturnType() == FT->getParamType(0),
+            "Return type does not match source type", IF);
+    Assert1(FT->getReturnType() == Type::ULongTy,
+            "Return type is not ulong!", IF);
+    NumArgs = 1;
+    break;    
+    
   case Intrinsic::ctpop:
   case Intrinsic::ctlz:
   case Intrinsic::cttz: