[RISCV] Store RVC and TSO ELF flags explicitly in RISCVTargetStreamer. NFCI (#83344)

Instead of caching STI in the RISCVELFTargetStreamer, store the two
flags we need from it.

My goal is to allow RISCVAsmPrinter to override these flags using IR
module metadata for LTO. So they need to be separated from the STI used
to construct the TargetStreamer.

This patch should be NFC as long as no one is changing the contents of
the STI that was used to construct the TargetStreamer between the
constructor and the use of the flags.

diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
index 961b8f0afe2254b584a8901b8ccf28f597ad1f17..cdf7c048a4bf1183e1e7cfde7131023959a62fee 100644 (file)
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
@@ -31,12 +31,13 @@ using namespace llvm;
 // This part is for ELF object output.
 RISCVTargetELFStreamer::RISCVTargetELFStreamer(MCStreamer &S,
                                                const MCSubtargetInfo &STI)
-    : RISCVTargetStreamer(S), CurrentVendor("riscv"), STI(STI) {
+    : RISCVTargetStreamer(S), CurrentVendor("riscv") {
   MCAssembler &MCA = getStreamer().getAssembler();
   const FeatureBitset &Features = STI.getFeatureBits();
   auto &MAB = static_cast<RISCVAsmBackend &>(MCA.getBackend());
   setTargetABI(RISCVABI::computeTargetABI(STI.getTargetTriple(), Features,
                                           MAB.getTargetOptions().getABIName()));
+  setFlagsFromFeatures(STI);
   // `j label` in `.option norelax; j label; .option relax; ...; label:` needs a
   // relocation to ensure the jump target is correct after linking. This is due
   // to a limitation that shouldForceRelocation has to make the decision upfront
@@ -87,14 +88,13 @@ 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 (hasRVC())
     EFlags |= ELF::EF_RISCV_RVC;
-  if (Features[RISCV::FeatureStdExtZtso])
+  if (hasTSO())
     EFlags |= ELF::EF_RISCV_TSO;
 
   switch (ABI) {

diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
index a6f54bf67b5d2bbfc612cc7427baa3fc31e2a17e..e8f29cd8449ba0bf9bafe17f40c3f71a12ae451c 100644 (file)
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
@@ -46,7 +46,6 @@ private:
   StringRef CurrentVendor;
 
   MCSection *AttributeSection = nullptr;
-  const MCSubtargetInfo &STI;
 
   void emitAttribute(unsigned Attribute, unsigned Value) override;
   void emitTextAttribute(unsigned Attribute, StringRef String) override;

diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.cpp
index ac4861bf113eb2ab4a9b3e15e88195f31bfa10f0..eee78a8c161f08a6705b8cd920f63426c76da222 100644 (file)
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.cpp
@@ -48,6 +48,11 @@ void RISCVTargetStreamer::setTargetABI(RISCVABI::ABI ABI) {
   TargetABI = ABI;
 }
 
+void RISCVTargetStreamer::setFlagsFromFeatures(const MCSubtargetInfo &STI) {
+  HasRVC = STI.hasFeature(RISCV::FeatureStdExtC);
+  HasTSO = STI.hasFeature(RISCV::FeatureStdExtZtso);
+}
+
 void RISCVTargetStreamer::emitTargetAttributes(const MCSubtargetInfo &STI,
                                                bool EmitStackAlign) {
   if (EmitStackAlign) {

diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.h b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.h
index 070e72fb157ae9cc030880715ff530c57445176b..cb8bc21cb635576c3ed481e59ec1a326c9da1f7a 100644 (file)
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.h
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVTargetStreamer.h
@@ -33,6 +33,8 @@ struct RISCVOptionArchArg {
 
 class RISCVTargetStreamer : public MCTargetStreamer {
   RISCVABI::ABI TargetABI = RISCVABI::ABI_Unknown;
+  bool HasRVC = false;
+  bool HasTSO = false;
 
 public:
   RISCVTargetStreamer(MCStreamer &S);
@@ -58,6 +60,9 @@ public:
   void emitTargetAttributes(const MCSubtargetInfo &STI, bool EmitStackAlign);
   void setTargetABI(RISCVABI::ABI ABI);
   RISCVABI::ABI getTargetABI() const { return TargetABI; }
+  void setFlagsFromFeatures(const MCSubtargetInfo &STI);
+  bool hasRVC() const { return HasRVC; }
+  bool hasTSO() const { return HasTSO; }
 };
 
 // This part is for ascii assembly output