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
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 @@
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 @@
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 @@
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])) {