[RISCV] Set the RVC bit in the ELF EFlags for C or Zca. (#80913)

Author: topperc

llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp

@@ -87,14 +87,14 @@ void RISCVTargetELFStreamer::finishAttributeSection() {
 void RISCVTargetELFStreamer::finish() {
   RISCVTargetStreamer::finish();
   MCAssembler &MCA = getStreamer().getAssembler();
-  const FeatureBitset &Features = STI.getFeatureBits();
   RISCVABI::ABI ABI = getTargetABI();
 
   unsigned EFlags = MCA.getELFHeaderEFlags();
 
-  if (Features[RISCV::FeatureStdExtC])
+  if (STI.hasFeature(RISCV::FeatureStdExtC) ||
+      STI.hasFeature(RISCV::FeatureStdExtZca))
     EFlags |= ELF::EF_RISCV_RVC;
-  if (Features[RISCV::FeatureStdExtZtso])
+  if (STI.hasFeature(RISCV::FeatureStdExtZtso))
     EFlags |= ELF::EF_RISCV_TSO;
 
   switch (ABI) {

llvm/test/MC/RISCV/elf-flags.s

@@ -2,6 +2,8 @@
 # RUN: llvm-mc -triple=riscv64 -filetype=obj < %s | llvm-readobj --file-headers - | FileCheck -check-prefixes=CHECK-RVI %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+c -filetype=obj < %s | llvm-readobj --file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
 # RUN: llvm-mc -triple=riscv64 -mattr=+c -filetype=obj < %s | llvm-readobj --file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
+# RUN: llvm-mc -triple=riscv32 -mattr=+zca -filetype=obj < %s | llvm-readobj --file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
+# RUN: llvm-mc -triple=riscv64 -mattr=+zca -filetype=obj < %s | llvm-readobj --file-headers - | FileCheck -check-prefixes=CHECK-RVIC %s
 # RUN: llvm-mc -triple=riscv32 -mattr=+e -filetype=obj < %s \
 # RUN:   | llvm-readobj --file-headers - \
 # RUN:   | FileCheck -check-prefix=CHECK-RVE %s