[Mips] TargetStreamer ELF flag Support for default and commandline options.

This patch uses a common MipsTargetSteamer interface for both 
MipsAsmPrinter and MipsAsmParser for recording default and commandline
driven directives that affect ELF header flags.

It has been noted that the .ll tests affected by this patch belong in
test/Codegen/Mips. I will move them in a separate patch.

Also, a number of directives do not get expressed by AsmPrinter in the 
resultant .s assembly such as setting the correct ASI. I have noted this
in the tests and they will be addressed in later patches.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200051 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -21,6 +21,9 @@
 #include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/MC/MCSymbol.h"
 #include "llvm/MC/MCTargetAsmParser.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/ADT/APInt.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/TargetRegistry.h"
 
@@ -194,7 +197,6 @@ class MipsAsmParser : public MCTargetAsmParser {
 
   bool isEvaluated(const MCExpr *Expr);
   bool parseDirectiveSet();
-  bool parseDirectiveMipsHackELFFlags();
   bool parseDirectiveOption();
 
   bool parseSetAtDirective();
@@ -257,6 +259,9 @@ class MipsAsmParser : public MCTargetAsmParser {
   // Example: INSERT.B $w0[n], $1 => 16 > n >= 0
   bool validateMSAIndex(int Val, int RegKind);
 
+  // Set ELF flags based on defaults and commandline arguments.
+  void processInitialEFlags();
+
 public:
   MipsAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser,
                 const MCInstrInfo &MII)
@@ -264,6 +269,7 @@ public:
         hasConsumedDollar(false) {
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(STI.getFeatureBits()));
+    processInitialEFlags();
   }
 
   MCAsmParser &getParser() const { return Parser; }
@@ -2429,17 +2435,6 @@ bool MipsAsmParser::parseDirectiveSet() {
   return true;
 }
 
-bool MipsAsmParser::parseDirectiveMipsHackELFFlags() {
-  int64_t Flags = 0;
-  if (Parser.parseAbsoluteExpression(Flags)) {
-    TokError("unexpected token");
-    return false;
-  }
-
-  getTargetStreamer().emitMipsHackELFFlags(Flags);
-  return false;
-}
-
 /// parseDirectiveWord
 ///  ::= .word [ expression (, expression)* ]
 bool MipsAsmParser::parseDirectiveWord(unsigned Size, SMLoc L) {
@@ -2558,9 +2553,6 @@ bool MipsAsmParser::ParseDirective(AsmToken DirectiveID) {
     return false;
   }
 
-  if (IDVal == ".mips_hack_elf_flags")
-    return parseDirectiveMipsHackELFFlags();
-
   if (IDVal == ".option")
     return parseDirectiveOption();
 
@@ -2577,6 +2569,43 @@ bool MipsAsmParser::ParseDirective(AsmToken DirectiveID) {
   return true;
 }
 
+void MipsAsmParser::processInitialEFlags() {
+  // Start will a clean slate.
+  unsigned EFlags = 0;
+  unsigned FeatureBits = STI.getFeatureBits();
+
+  // Default settings
+  EFlags |= ELF::EF_MIPS_NOREORDER | ELF::EF_MIPS_PIC | ELF::EF_MIPS_ABI_O32;
+
+  // ISA
+  if (FeatureBits & Mips::FeatureMips64r2) {
+    EFlags |= ELF::EF_MIPS_ARCH_64R2;
+    EFlags &= ~ELF::EF_MIPS_ABI_O32;
+  } else if (FeatureBits & Mips::FeatureMips64) {
+    EFlags |= ELF::EF_MIPS_ARCH_64;
+    EFlags &= ~ELF::EF_MIPS_ABI_O32;
+  } else if (FeatureBits & Mips::FeatureMips32r2)
+    EFlags |= ELF::EF_MIPS_ARCH_32R2;
+  else if (FeatureBits & Mips::FeatureMips32)
+    EFlags |= ELF::EF_MIPS_ARCH_32;
+  else if (FeatureBits & Mips::FeatureO32)
+    EFlags |= ELF::EF_MIPS_ABI_O32; // This is really a zero
+
+  // ASE
+  if (FeatureBits & Mips::FeatureMicroMips)
+    EFlags |= ELF::EF_MIPS_MICROMIPS;
+  else if (FeatureBits & Mips::FeatureMips16)
+    EFlags |= ELF::EF_MIPS_ARCH_ASE_M16;
+
+  // ABI
+  // TODO: n32/eabi
+
+  // Linkage model
+  // TODO: pic/cpic/static
+
+  getTargetStreamer().emitMipsELFFlags(EFlags);
+}
+
 extern "C" void LLVMInitializeMipsAsmParser() {
   RegisterMCAsmParser<MipsAsmParser> X(TheMipsTarget);
   RegisterMCAsmParser<MipsAsmParser> Y(TheMipselTarget);

lib/Target/Mips/MCTargetDesc/MipsTargetStreamer.cpp

@@ -21,23 +21,13 @@
 
 using namespace llvm;
 
-static cl::opt<bool> PrintHackDirectives("print-hack-directives",
-                                         cl::init(false), cl::Hidden);
-
 // Pin vtable to this file.
 void MipsTargetStreamer::anchor() {}
 
 MipsTargetAsmStreamer::MipsTargetAsmStreamer(formatted_raw_ostream &OS)
     : OS(OS) {}
 
-void MipsTargetAsmStreamer::emitMipsHackELFFlags(unsigned Flags) {
-  if (!PrintHackDirectives)
-    return;
-
-  OS << "\t.mips_hack_elf_flags 0x";
-  OS.write_hex(Flags);
-  OS << '\n';
-}
+void MipsTargetAsmStreamer::emitMipsELFFlags(unsigned Flags) { return; }
 
 void MipsTargetAsmStreamer::emitDirectiveSetMicroMips() {
   OS << "\t.set\tmicromips\n";
@@ -85,7 +75,7 @@ MCELFStreamer &MipsTargetELFStreamer::getStreamer() {
   return static_cast<MCELFStreamer &>(*Streamer);
 }
 
-void MipsTargetELFStreamer::emitMipsHackELFFlags(unsigned Flags) {
+void MipsTargetELFStreamer::emitMipsELFFlags(unsigned Flags) {
   MCAssembler &MCA = getStreamer().getAssembler();
   MCA.setELFHeaderEFlags(Flags);
 }

lib/Target/Mips/MipsAsmPrinter.cpp

@@ -108,7 +108,6 @@ void MipsAsmPrinter::EmitInstruction(const MachineInstr *MI) {
     return;
   }
 
-
   MachineBasicBlock::const_instr_iterator I = MI;
   MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end();
 
@@ -634,8 +633,12 @@ void MipsAsmPrinter::EmitStartOfAsmFile(Module &M) {
 
 }
 
-static void emitELFHeaderFlagsCG(MipsTargetStreamer &TargetStreamer,
-                                 const MipsSubtarget &Subtarget) {
+void MipsAsmPrinter::processInitialEFlags() {
+  // Not having this check would work too, but would have us chew through
+  // code that it doesn't use for RawText.
+  if (OutStreamer.hasRawTextSupport())
+    return;
+
   // Update e_header flags
   unsigned EFlags = 0;
 
@@ -643,30 +646,30 @@ static void emitELFHeaderFlagsCG(MipsTargetStreamer &TargetStreamer,
   // Currently we assume that -mabicalls is the default.
   EFlags |= ELF::EF_MIPS_CPIC;
 
-  if (Subtarget.inMips16Mode())
+  if (Subtarget->inMips16Mode())
     EFlags |= ELF::EF_MIPS_ARCH_ASE_M16;
   else
     EFlags |= ELF::EF_MIPS_NOREORDER;
 
   // Architecture
-  if (Subtarget.hasMips64r2())
+  if (Subtarget->hasMips64r2())
     EFlags |= ELF::EF_MIPS_ARCH_64R2;
-  else if (Subtarget.hasMips64())
+  else if (Subtarget->hasMips64())
     EFlags |= ELF::EF_MIPS_ARCH_64;
-  else if (Subtarget.hasMips32r2())
+  else if (Subtarget->hasMips32r2())
     EFlags |= ELF::EF_MIPS_ARCH_32R2;
   else
     EFlags |= ELF::EF_MIPS_ARCH_32;
 
-  if (Subtarget.inMicroMipsMode())
+  if (Subtarget->inMicroMipsMode())
     EFlags |= ELF::EF_MIPS_MICROMIPS;
 
   // ABI
-  if (Subtarget.isABI_O32())
+  if (Subtarget->isABI_O32())
     EFlags |= ELF::EF_MIPS_ABI_O32;
 
   // Relocation Model
-  Reloc::Model RM = Subtarget.getRelocationModel();
+  Reloc::Model RM = Subtarget->getRelocationModel();
   if (RM == Reloc::PIC_ || RM == Reloc::Default)
     EFlags |= ELF::EF_MIPS_PIC;
   else if (RM == Reloc::Static)
@@ -674,14 +677,13 @@ static void emitELFHeaderFlagsCG(MipsTargetStreamer &TargetStreamer,
   else
     llvm_unreachable("Unsupported relocation model for e_flags");
 
-  TargetStreamer.emitMipsHackELFFlags(EFlags);
+  getTargetStreamer().emitMipsELFFlags(EFlags);
 }
 
 void MipsAsmPrinter::EmitEndOfAsmFile(Module &M) {
   // Emit Mips ELF register info
   Subtarget->getMReginfo().emitMipsReginfoSectionCG(
              OutStreamer, getObjFileLowering(), *Subtarget);
-  emitELFHeaderFlagsCG(getTargetStreamer(), *Subtarget);
 }
 
 void MipsAsmPrinter::PrintDebugValueComment(const MachineInstr *MI,

lib/Target/Mips/MipsAsmPrinter.h

@@ -50,6 +50,10 @@ private:
   /// pool entries so we can properly mark them as data regions.
   bool InConstantPool;
 
+  // If object output, set initial eflags.
+  // This includes both default and commandline flags that affect the output
+  // ELF header flags.
+  void processInitialEFlags();
 
 public:
 
@@ -61,6 +65,7 @@ public:
     : AsmPrinter(TM, Streamer), MCP(0), InConstantPool(false),
       MCInstLowering(*this) {
     Subtarget = &TM.getSubtarget<MipsSubtarget>();
+    processInitialEFlags();
   }
 
   virtual const char *getPassName() const {
@@ -103,6 +108,7 @@ public:
   void EmitStartOfAsmFile(Module &M);
   void EmitEndOfAsmFile(Module &M);
   void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
+
 };
 }
 

lib/Target/Mips/MipsTargetStreamer.h

@@ -18,7 +18,7 @@ class MipsTargetStreamer : public MCTargetStreamer {
   virtual void anchor();
 
 public:
-  virtual void emitMipsHackELFFlags(unsigned Flags) = 0;
+  virtual void emitMipsELFFlags(unsigned Flags) = 0;
   virtual void emitDirectiveSetMicroMips() = 0;
   virtual void emitDirectiveSetNoMicroMips() = 0;
   virtual void emitDirectiveSetMips16() = 0;
@@ -34,7 +34,7 @@ class MipsTargetAsmStreamer : public MipsTargetStreamer {
 
 public:
   MipsTargetAsmStreamer(formatted_raw_ostream &OS);
-  virtual void emitMipsHackELFFlags(unsigned Flags);
+  virtual void emitMipsELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();
@@ -56,7 +56,7 @@ public:
   virtual void emitLabel(MCSymbol *Symbol) LLVM_OVERRIDE;
 
   // FIXME: emitMipsHackELFFlags() will be removed from this class.
-  virtual void emitMipsHackELFFlags(unsigned Flags);
+  virtual void emitMipsELFFlags(unsigned Flags);
   virtual void emitDirectiveSetMicroMips();
   virtual void emitDirectiveSetNoMicroMips();
   virtual void emitDirectiveSetMips16();

test/MC/Mips/elf_eflags.ll

@@ -1,6 +1,5 @@
-; This tests ELF EFLAGS setting with direct object.
-; When the assembler is ready a .s file for it will
-; be created.
+; This tests for directives that will result in
+; ELF EFLAGS setting with direct object.
 
 ; Non-shared (static) is the absence of pic and or cpic.
 
@@ -16,52 +15,105 @@
 ; Note that EF_MIPS_CPIC is set by -mabicalls which is the default on Linux
 ; TODO need to support -mno-abicalls
 
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32 -relocation-model=static %s -print-hack-directives -o - | FileCheck -check-prefix=CHECK-BE32 %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32 -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE32_PIC %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -relocation-model=static %s -print-hack-directives -o - | FileCheck -check-prefix=CHECK-BE32R2 %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE32R2_PIC %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -mattr=+micromips -relocation-model=static -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE32R2-MICROMIPS %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -mattr=+micromips -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE32R2-MICROMIPS_PIC %s
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32 \
+; RUN: -relocation-model=static %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32 %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32 %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32_PIC %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 \
+; RUN: -relocation-model=static %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32R2 %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32R2_PIC %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 \
+; RUN: -mattr=+micromips -relocation-model=static %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32R2-MICROMIPS %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 \
+; RUN: -mattr=+micromips %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE32R2-MICROMIPS_PIC %s
 
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64 -relocation-model=static %s -print-hack-directives -o - | FileCheck -check-prefix=CHECK-BE64 %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64 %s -print-hack-directives -o - | FileCheck -check-prefix=CHECK-BE64_PIC %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64r2 -relocation-model=static -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE64R2 %s
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64r2 -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-BE64R2_PIC %s
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64 \
+; RUN: -relocation-model=static %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE64 %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64 %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE64_PIC %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64r2 \
+; RUN: -relocation-model=static %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE64R2 %s
+;
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips64r2 %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-BE64R2_PIC %s
 
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -mattr=+mips16 -relocation-model=pic -print-hack-directives %s -o - | FileCheck -check-prefix=CHECK-LE32R2-MIPS16 %s
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 \
+; RUN: -mattr=+mips16 -relocation-model=pic %s -o - | \
+; RUN: FileCheck -check-prefix=CHECK-LE32R2-MIPS16 %s
 
 ; 32(R1) bit with NO_REORDER and static
-; CHECK-BE32: .mips_hack_elf_flags 0x50001005
+; CHECK-BE32: .abicalls
+; CHECK-BE32: .option pic0
+; CHECK-BE32: .set noreorder
+; TODO: Need .set mips32
 ;
 ; 32(R1) bit with NO_REORDER and PIC
-; CHECK-BE32_PIC: .mips_hack_elf_flags 0x50001007
+; CHECK-BE32_PIC: .abicalls
+; CHECK-BE32_PIC: .set noreorder
+; TODO: Need .set mips32 and check absence of .option pic0
 ;
 ; 32R2 bit with NO_REORDER and static
-; CHECK-BE32R2: .mips_hack_elf_flags 0x70001005
+; CHECK-BE32R2: .abicalls
+; CHECK-BE32R2: .option pic0
+; CHECK-BE32R2: .set noreorder
+; TODO: Need .set mips32r2
 ;
 ; 32R2 bit with NO_REORDER and PIC
-; CHECK-BE32R2_PIC: .mips_hack_elf_flags 0x70001007
+; CHECK-BE32R2_PIC:.abicalls
+; CHECK-BE32R2_PIC:.set noreorder
+; TODO: Need .set mips32r2 and check absence of .option pic0
 ;
 ; 32R2 bit MICROMIPS with NO_REORDER and static
-; CHECK-BE32R2-MICROMIPS: .mips_hack_elf_flags 0x72001005
+; CHECK-BE32R2-MICROMIPS: .abicalls
+; CHECK-BE32R2-MICROMIPS: .option pic0
+; CHECK-BE32R2-MICROMIPS: .set micromips
+; CHECK-BE32R2-MICROMIPS: .set noreorder
+; TODO: Need .set mips32r2
 ;
 ; 32R2 bit MICROMIPS with NO_REORDER and PIC
-; CHECK-BE32R2-MICROMIPS_PIC: .mips_hack_elf_flags 0x72001007
+; CHECK-BE32R2-MICROMIPS_PIC: .abicalls
+; CHECK-BE32R2-MICROMIPS_PIC: .set micromips
+; CHECK-BE32R2-MICROMIPS_PIC: .set noreorder
+; TODO: Need .set mips32r2 and check absence of .option pic0
 ;
 ; 64(R1) bit with NO_REORDER and static
-; CHECK-BE64: .mips_hack_elf_flags 0x60000005
+; CHECK-BE64: .abicalls
+; CHECK-BE64: .set noreorder
+; TODO: Need .set mips64 and .option pic0
 ;
 ; 64(R1) bit with NO_REORDER and PIC
-; CHECK-BE64_PIC: .mips_hack_elf_flags 0x60000007
+; CHECK-BE64_PIC: .abicalls
+; CHECK-BE64_PIC: .set noreorder
+; TODO: Need .set mips64 and check absence of .option pic0
 ;
 ; 64R2 bit with NO_REORDER and static
-; CHECK-BE64R2: .mips_hack_elf_flags 0x80000005
+; CHECK-BE64R2: .abicalls
+; CHECK-BE64R2: .set noreorder
+; TODO: Need .set mips64r2 and .option pic0
 ;
 ; 64R2 bit with NO_REORDER and PIC
-; CHECK-BE64R2_PIC: .mips_hack_elf_flags 0x80000007
+; CHECK-BE64R2_PIC: .abicalls
+; CHECK-BE64R2_PIC: .set noreorder
+; TODO: Need .set mips64r2 and check absence of .option pic0
 ;
 ; 32R2 bit MIPS16 with PIC
-; CHECK-LE32R2-MIPS16: .mips_hack_elf_flags 0x74001006
+; CHECK-LE32R2-MIPS16: .abicalls
+; CHECK-LE32R2-MIPS16: .set mips16
+; TODO: Need .set mips32r2 and check absence of .option pic0 and noreorder
 
 define i32 @main() nounwind {
 entry:

test/MC/Mips/elf_eflags.s

@@ -1,15 +1,21 @@
-// RUN: llvm-mc -filetype=obj -triple mipsel-unknown-linux %s -o -| llvm-readobj -h | FileCheck %s
-// The initial value will be set at 0x50001003 and
-// we will override that with the negation of 0x2 (option pic0
-// the addition of 0x4 (.abicalls)
+// RUN: llvm-mc -filetype=obj -triple mipsel-unknown-linux %s -o - | \
+// RUN: llvm-readobj -h | FileCheck %s
 
-        .mips_hack_elf_flags 0x50001003
+// From the commandline and defaults the following should be set:
+//   EF_MIPS_ARCH_32      (0x50000000)
+//   EF_MIPS_ABI_O32      (0x00001000)
+//   EF_MIPS_NOREORDER    (0x00000001)
+//   EF_MIPS_PIC          (0x00000002)
+
+// Inline directives should set or unset the following:
+//   EF_MIPS_CPIC         (0x00000004) : .abicalls
+//   EF_MIPS_ARCH_ASE_M16 (0x04000000) : .set mips16
+//   The negation of EF_MIPS_PIC : .option pic0
 
 // CHECK: Flags [ (0x54001005)
 
         .abicalls
 
         .option pic0
- 
- // Set EF_MIPS_ARCH_ASE_M16 (0x04000000)
+
         .set mips16

test/MC/Mips/elf_st_other.ll

@@ -1,12 +1,13 @@
 ; This tests value of ELF st_other field for function symbol table entries.
 ; For microMIPS value should be equal to STO_MIPS_MICROMIPS.
 
-; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -mattr=+micromips -print-hack-directives %s -o - | FileCheck %s
+; RUN: llc -mtriple mipsel-unknown-linux -mcpu=mips32r2 -mattr=+micromips %s \
+; RUN: -o - | FileCheck %s
 
 define i32 @main() nounwind {
 entry:
   ret i32 0
 }
 
-; CHECK: .set	micromips
+; CHECK: .set micromips
 ; CHECK: main: