[clang] [llvm] [RISC-V] Make EmitRISCVCpuSupports accept multiple features (PR #104917)

[Craig Topper via llvm-commits]

================
@@ -14439,33 +14440,60 @@ Value *CodeGenFunction::EmitRISCVCpuSupports(const CallExpr *E) {
   if (!getContext().getTargetInfo().validateCpuSupports(FeatureStr))
     return Builder.getFalse();
 
-  // Note: We are making an unchecked assumption that the size of the
-  // feature array is >= 1.  This holds for any version of compiler-rt
-  // which defines this interface.
-  llvm::ArrayType *ArrayOfInt64Ty = llvm::ArrayType::get(Int64Ty, 1);
+  return EmitRISCVCpuSupports(ArrayRef<StringRef>(FeatureStr));
+}
+
+static Value *loadRISCVFeatureBits(unsigned Index, CGBuilderTy &Builder,
+                                   CodeGenModule &CGM,
+                                   llvm::LLVMContext &Context) {
+  llvm::Type *Int32Ty = llvm::Type::getInt32Ty(Context);
+  llvm::Type *Int64Ty = llvm::Type::getInt64Ty(Context);
+  llvm::ArrayType *ArrayOfInt64Ty =
+      llvm::ArrayType::get(Int64Ty, llvm::RISCV::RISCVFeatureBitSize);
   llvm::Type *StructTy = llvm::StructType::get(Int32Ty, ArrayOfInt64Ty);
   llvm::Constant *RISCVFeaturesBits =
       CGM.CreateRuntimeVariable(StructTy, "__riscv_feature_bits");
-  auto *GV = cast<llvm::GlobalValue>(RISCVFeaturesBits);
-  GV->setDSOLocal(true);
-
-  auto LoadFeatureBit = [&](unsigned Index) {
-    // Create GEP then load.
-    Value *IndexVal = llvm::ConstantInt::get(Int32Ty, Index);
-    llvm::Value *GEPIndices[] = {Builder.getInt32(0), Builder.getInt32(1),
-                                 IndexVal};
-    Value *Ptr =
-        Builder.CreateInBoundsGEP(StructTy, RISCVFeaturesBits, GEPIndices);
-    Value *FeaturesBit =
-        Builder.CreateAlignedLoad(Int64Ty, Ptr, CharUnits::fromQuantity(8));
-    return FeaturesBit;
-  };
+  cast<llvm::GlobalValue>(RISCVFeaturesBits)->setDSOLocal(true);
+  Value *IndexVal = llvm::ConstantInt::get(Int32Ty, Index);
+  llvm::Value *GEPIndices[] = {Builder.getInt32(0), Builder.getInt32(1),
+                               IndexVal};
+  Value *Ptr =
+      Builder.CreateInBoundsGEP(StructTy, RISCVFeaturesBits, GEPIndices);
+  Value *FeaturesBit =
+      Builder.CreateAlignedLoad(Int64Ty, Ptr, CharUnits::fromQuantity(8));
+  return FeaturesBit;
+}
+
+Value *CodeGenFunction::EmitRISCVCpuSupports(ArrayRef<StringRef> FeaturesStrs) {
+  const unsigned RISCVFeatureLength = llvm::RISCV::RISCVFeatureBitSize;
+  SmallVector<uint64_t, 2> RequireBitMasks(RISCVFeatureLength);
----------------
topperc wrote:

Can this be a plain array since the size is constant?

https://github.com/llvm/llvm-project/pull/104917