Iasm and obj lowering for advanced switch lowering.

src/IceTargetLoweringX8632.cpp

 //===- subzero/src/IceTargetLoweringX8632.cpp - x86-32 lowering -----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 133 matching lines @@
   static const Type Ty = IceType_i8;
   static const char *TypeName;
   static const char *AsmTag;
   static const char *PrintfString;
 };
 const char *PoolTypeConverter<uint8_t>::TypeName = "i8";
 const char *PoolTypeConverter<uint8_t>::AsmTag = ".byte";
 const char *PoolTypeConverter<uint8_t>::PrintfString = "0x%x";
 } // end of anonymous namespace
 
+void TargetX8632::emitJumpTable(const Cfg *Func,
+                                const InstJumpTable *JumpTable) const {
+  if (!BuildDefs::dump())
+    return;
+  Ostream &Str = Ctx->getStrEmit();
+  IceString MangledName = Ctx->mangleName(Func->getFunctionName());
+  Str << "\t.section\t.rodata." << MangledName
+      << "$jumptable,\"a\",@progbits\n";
+  Str << "\t.align\t" << typeWidthInBytes(getPointerType()) << "\n";
+  Str << InstJumpTable::makeName(MangledName, JumpTable->getId()) << ":";
+
+  // On X8632 pointers are 32-bit hence the use of .long
+  for (SizeT I = 0; I < JumpTable->getNumTargets(); ++I)
+    Str << "\n\t.long\t" << JumpTable->getTarget(I)->getAsmName();
+  Str << "\n";
+}
+
 template <typename T>
 void TargetDataX8632::emitConstantPool(GlobalContext *Ctx) {
   if (!BuildDefs::dump())
     return;
   Ostream &Str = Ctx->getStrEmit();
   Type Ty = T::Ty;
   SizeT Align = typeAlignInBytes(Ty);
   ConstantList Pool = Ctx->getConstantPool(Ty);
 
   Str << "\t.section\t.rodata.cst" << Align << ",\"aM\",@progbits," << Align
@@ skipping 51 matching lines @@
     emitConstantPool<PoolTypeConverter<uint8_t>>(Ctx);
     emitConstantPool<PoolTypeConverter<uint16_t>>(Ctx);
     emitConstantPool<PoolTypeConverter<uint32_t>>(Ctx);
 
     emitConstantPool<PoolTypeConverter<float>>(Ctx);
     emitConstantPool<PoolTypeConverter<double>>(Ctx);
   } break;
   }
 }
 
+void TargetDataX8632::lowerJumpTables() {
+  switch (Ctx->getFlags().getOutFileType()) {
+  case FT_Elf: {
+    ELFObjectWriter *Writer = Ctx->getObjectWriter();
+    for (const JumpTableData &JumpTable : *Ctx->getJumpTables())
+      Writer->writeJumpTable(JumpTable, llvm::ELF::R_386_32);
+  } break;
+  case FT_Asm:
+    // Already emitted from Cfg
+    break;
+  case FT_Iasm: {
+    if (!BuildDefs::dump())
+      return;
+    Ostream &Str = Ctx->getStrEmit();
+    for (const JumpTableData &JT : *Ctx->getJumpTables()) {
+      Str << "\t.section\t.rodata." << JT.getFunctionName()
+          << "$jumptable,\"a\",@progbits\n";
+      Str << "\t.align\t" << typeWidthInBytes(getPointerType()) << "\n";
+      Str << InstJumpTable::makeName(JT.getFunctionName(), JT.getId()) << ":";
+
+      // On X8632 pointers are 32-bit hence the use of .long
+      for (intptr_t TargetOffset : JT.getTargetOffsets())
+        Str << "\n\t.long\t" << JT.getFunctionName() << "+" << TargetOffset;
+      Str << "\n";
+    }
+  } break;
+  }
+}
+
 void TargetDataX8632::lowerGlobals(const VariableDeclarationList &Vars,
                                    const IceString &SectionSuffix) {
   switch (Ctx->getFlags().getOutFileType()) {
   case FT_Elf: {
     ELFObjectWriter *Writer = Ctx->getObjectWriter();
     Writer->writeDataSection(Vars, llvm::ELF::R_386_32, SectionSuffix);
   } break;
   case FT_Asm:
   case FT_Iasm: {
     const IceString &TranslateOnly = Ctx->getFlags().getTranslateOnly();
@@ skipping 112 matching lines @@
 // entries in case the high-level table has extra entries.
 #define X(tag, sizeLog2, align, elts, elty, str)                               \
   static_assert(_table1_##tag == _table2_##tag,                                \
                 "Inconsistency between ICETYPEX8632_TABLE and ICETYPE_TABLE");
 ICETYPE_TABLE
 #undef X
 } // end of namespace dummy3
 } // end of anonymous namespace
 
 } // end of namespace Ice