Recognise 32-bit ror-based bswap implementation used by uclibc
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119007 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index c82254c..1c5c510 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -11451,6 +11451,35 @@
}
break;
case 3:
+ if (CI->getType()->isIntegerTy(32) &&
+ IA->getConstraintString().compare(0, 5, "=r,0,") == 0) {
+ SmallVector<StringRef, 4> Words;
+ SplitString(AsmPieces[0], Words, " \t,");
+ if (Words.size() == 3 && Words[0] == "rorw" && Words[1] == "$$8" &&
+ Words[2] == "${0:w}") {
+ Words.clear();
+ SplitString(AsmPieces[1], Words, " \t,");
+ if (Words.size() == 3 && Words[0] == "rorl" && Words[1] == "$$16" &&
+ Words[2] == "$0") {
+ Words.clear();
+ SplitString(AsmPieces[2], Words, " \t,");
+ if (Words.size() == 3 && Words[0] == "rorw" && Words[1] == "$$8" &&
+ Words[2] == "${0:w}") {
+ AsmPieces.clear();
+ const std::string &Constraints = IA->getConstraintString();
+ SplitString(StringRef(Constraints).substr(5), AsmPieces, ",");
+ std::sort(AsmPieces.begin(), AsmPieces.end());
+ if (AsmPieces.size() == 4 &&
+ AsmPieces[0] == "~{cc}" &&
+ AsmPieces[1] == "~{dirflag}" &&
+ AsmPieces[2] == "~{flags}" &&
+ AsmPieces[3] == "~{fpsr}") {
+ return LowerToBSwap(CI);
+ }
+ }
+ }
+ }
+ }
if (CI->getType()->isIntegerTy(64) &&
Constraints.size() >= 2 &&
Constraints[0].Codes.size() == 1 && Constraints[0].Codes[0] == "A" &&