[RISCV] Add Clang frontend support for Bitmanip extension

Summary: This adds the __riscv_bitmanip macro and the 'b' target feature to enable it.

Reviewers: asb, simoncook, lewis-revill, PaoloS, lenary

Reviewed By: lenary

Subscribers: Jim, rbar, johnrusso, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, pzheng, sameer.abuasal, apazos, luismarques, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71553

2 files changed, 9 insertions, 1 deletions

diff --git a/clang/lib/Basic/Targets/RISCV.cpp b/clang/lib/Basic/Targets/RISCV.cpp
index ab8272c034f..58285f1d813 100644
--- a/clang/lib/Basic/Targets/RISCV.cpp
+++ b/clang/lib/Basic/Targets/RISCV.cpp
@@ -125,6 +125,10 @@ void RISCVTargetInfo::getTargetDefines(const LangOptions &Opts,
 
   if (HasC)
     Builder.defineMacro("__riscv_compressed");
+
+  if (HasB) {
+    Builder.defineMacro("__riscv_bitmanip");
+  }
 }
 
 /// Return true if has this feature, need to sync with handleTargetFeatures.
@@ -139,6 +143,7 @@ bool RISCVTargetInfo::hasFeature(StringRef Feature) const {
       .Case("f", HasF)
       .Case("d", HasD)
       .Case("c", HasC)
+      .Case("b", HasB)
       .Default(false);
 }
 
@@ -156,6 +161,8 @@ bool RISCVTargetInfo::handleTargetFeatures(std::vector<std::string> &Features,
       HasD = true;
     else if (Feature == "+c")
       HasC = true;
+    else if (Feature == "+b")
+      HasB = true;
   }
 
   return true;
diff --git a/clang/lib/Basic/Targets/RISCV.h b/clang/lib/Basic/Targets/RISCV.h
index 9118494a87a..05da13230bf 100644
--- a/clang/lib/Basic/Targets/RISCV.h
+++ b/clang/lib/Basic/Targets/RISCV.h
@@ -30,11 +30,12 @@ protected:
   bool HasF;
   bool HasD;
   bool HasC;
+  bool HasB;
 
 public:
   RISCVTargetInfo(const llvm::Triple &Triple, const TargetOptions &)
       : TargetInfo(Triple), HasM(false), HasA(false), HasF(false),
-        HasD(false), HasC(false) {
+        HasD(false), HasC(false), HasB(false) {
     LongDoubleWidth = 128;
     LongDoubleAlign = 128;
     LongDoubleFormat = &llvm::APFloat::IEEEquad();