[mips] Add MipsOptionRecord abstraction and use it to implement .reginfo/.MIPS.options

This abstraction allows us to support the various records that can be placed in
the .MIPS.options section in the future. We currently use it to record register
usage information (the ODK_REGINFO record in our ELF64 spec).

Each .MIPS.options record should subclass MipsOptionRecord and provide an
implementation of EmitMipsOptionRecord.

Patch by Matheus Almeida and Toma Tabacu

llvm-svn: 213522

1 files changed, 8 insertions, 41 deletions

diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
index 4e7216921b9..4a178e2df7a 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "InstPrinter/MipsInstPrinter.h"
+#include "MipsELFStreamer.h"
 #include "MipsMCTargetDesc.h"
 #include "MipsTargetObjectFile.h"
 #include "MipsTargetStreamer.h"
@@ -323,11 +324,7 @@ void MipsTargetELFStreamer::emitLabel(MCSymbol *Symbol) {
 
 void MipsTargetELFStreamer::finish() {
   MCAssembler &MCA = getStreamer().getAssembler();
-  MCContext &Context = MCA.getContext();
-  MCStreamer &OS = getStreamer();
-  const MCObjectFileInfo &OFI = *Context.getObjectFileInfo();
-  Triple T(STI.getTargetTriple());
-  uint64_t Features = STI.getFeatureBits();
+  const MCObjectFileInfo &OFI = *MCA.getContext().getObjectFileInfo();
 
   // .bss, .text and .data are always at least 16-byte aligned.
   MCSectionData &TextSectionData =
@@ -341,42 +338,12 @@ void MipsTargetELFStreamer::finish() {
   DataSectionData.setAlignment(std::max(16u, DataSectionData.getAlignment()));
   BSSSectionData.setAlignment(std::max(16u, BSSSectionData.getAlignment()));
 
-  if (T.isArch64Bit() && (Features & Mips::FeatureN64)) {
-    // The EntrySize value of 1 seems strange since the records are neither
-    // 1-byte long nor fixed length but it matches the value GAS emits.
-    const MCSectionELF *Sec =
-        Context.getELFSection(".MIPS.options", ELF::SHT_MIPS_OPTIONS,
-                              ELF::SHF_ALLOC | ELF::SHF_MIPS_NOSTRIP,
-                              SectionKind::getMetadata(), 1, "");
-    MCA.getOrCreateSectionData(*Sec).setAlignment(8);
-    OS.SwitchSection(Sec);
-
-    OS.EmitIntValue(1, 1);  // kind
-    OS.EmitIntValue(40, 1); // size
-    OS.EmitIntValue(0, 2);  // section
-    OS.EmitIntValue(0, 4);  // info
-    OS.EmitIntValue(0, 4);  // ri_gprmask
-    OS.EmitIntValue(0, 4);  // pad
-    OS.EmitIntValue(0, 4);  // ri_cpr[0]mask
-    OS.EmitIntValue(0, 4);  // ri_cpr[1]mask
-    OS.EmitIntValue(0, 4);  // ri_cpr[2]mask
-    OS.EmitIntValue(0, 4);  // ri_cpr[3]mask
-    OS.EmitIntValue(0, 8);  // ri_gp_value
-  } else {
-    const MCSectionELF *Sec =
-        Context.getELFSection(".reginfo", ELF::SHT_MIPS_REGINFO, ELF::SHF_ALLOC,
-                              SectionKind::getMetadata(), 24, "");
-    MCA.getOrCreateSectionData(*Sec)
-        .setAlignment(Features & Mips::FeatureN32 ? 8 : 4);
-    OS.SwitchSection(Sec);
-
-    OS.EmitIntValue(0, 4); // ri_gprmask
-    OS.EmitIntValue(0, 4); // ri_cpr[0]mask
-    OS.EmitIntValue(0, 4); // ri_cpr[1]mask
-    OS.EmitIntValue(0, 4); // ri_cpr[2]mask
-    OS.EmitIntValue(0, 4); // ri_cpr[3]mask
-    OS.EmitIntValue(0, 4); // ri_gp_value
-  }
+  // Emit all the option records.
+  // At the moment we are only emitting .Mips.options (ODK_REGINFO) and
+  // .reginfo.
+  MipsELFStreamer &MEF = static_cast<MipsELFStreamer &>(Streamer);
+  MEF.EmitMipsOptionRecords();
+
   emitMipsAbiFlags();
 }