* Fix one more bug in PIC codegen: extra load is needed for *all*
[oota-llvm.git] / lib / Target / X86 / X86AsmPrinter.cpp
index 1eb4460e69088f2a82222d1150b83d34ee20fead..bea3914fe649be3752c28655937186af58546e7d 100644 (file)
 
 #include "X86AsmPrinter.h"
 #include "X86ATTAsmPrinter.h"
+#include "X86COFF.h"
 #include "X86IntelAsmPrinter.h"
+#include "X86MachineFunctionInfo.h"
 #include "X86Subtarget.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/CallingConv.h"
 #include "llvm/Constants.h"
 #include "llvm/Module.h"
 #include "llvm/Type.h"
 #include "llvm/Assembly/Writer.h"
 #include "llvm/Support/Mangler.h"
-#include "llvm/Support/CommandLine.h"
+#include "llvm/Target/TargetAsmInfo.h"
+#include "llvm/Target/TargetOptions.h"
 using namespace llvm;
 
-Statistic<> llvm::EmittedInsts("asm-printer",
-                               "Number of machine instrs printed");
-
-enum AsmWriterFlavorTy { att, intel };
-cl::opt<AsmWriterFlavorTy>
-AsmWriterFlavor("x86-asm-syntax",
-                cl::desc("Choose style of code to emit from X86 backend:"),
-                cl::values(
-                           clEnumVal(att,   "  Emit AT&T-style assembly"),
-                           clEnumVal(intel, "  Emit Intel-style assembly"),
-                           clEnumValEnd),
-#ifdef _MSC_VER
-                cl::init(intel)
-#else
-                cl::init(att)
-#endif
-                );
-
-/// doInitialization
-bool X86SharedAsmPrinter::doInitialization(Module &M) {
-  const X86Subtarget *Subtarget = &TM.getSubtarget<X86Subtarget>();
+static X86FunctionInfo calculateFunctionInfo(const Function *F,
+                                             const TargetData *TD) {
+  X86FunctionInfo Info;
+  uint64_t Size = 0;
   
-  forDarwin = false;
-  PrivateGlobalPrefix = ".L";
+  switch (F->getCallingConv()) {
+  case CallingConv::X86_StdCall:
+    Info.setDecorationStyle(StdCall);
+    break;
+  case CallingConv::X86_FastCall:
+    Info.setDecorationStyle(FastCall);
+    break;
+  default:
+    return Info;
+  }
+
+  for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
+       AI != AE; ++AI)
+    Size += TD->getTypeSize(AI->getType());
+
+  // Size should be aligned to DWORD boundary
+  Size = ((Size + 3)/4)*4;
   
-  switch (Subtarget->TargetType) {
-  case X86Subtarget::isDarwin:
-    AlignmentIsInBytes = false;
-    GlobalPrefix = "_";
-    Data64bitsDirective = 0;       // we can't emit a 64-bit unit
-    ZeroDirective = "\t.space\t";  // ".space N" emits N zeros.
-    PrivateGlobalPrefix = "L";     // Marker for constant pool idxs
-    ConstantPoolSection = "\t.const\n";
-    JumpTableSection = "\t.const\n"; // FIXME: depends on PIC mode
-    LCOMMDirective = "\t.lcomm\t";
-    COMMDirectiveTakesAlignment = false;
-    HasDotTypeDotSizeDirective = false;
-    forDarwin = true;
-    StaticCtorsSection = ".mod_init_func";
-    StaticDtorsSection = ".mod_term_func";
-    InlineAsmStart = InlineAsmEnd = "";  // Don't use #APP/#NO_APP
+  // We're not supporting tooooo huge arguments :)
+  Info.setBytesToPopOnReturn((unsigned int)Size);
+  return Info;
+}
+
+
+/// decorateName - Query FunctionInfoMap and use this information for various
+/// name decoration.
+void X86SharedAsmPrinter::decorateName(std::string &Name,
+                                       const GlobalValue *GV) {
+  const Function *F = dyn_cast<Function>(GV);
+  if (!F) return;
+
+  // We don't want to decorate non-stdcall or non-fastcall functions right now
+  unsigned CC = F->getCallingConv();
+  if (CC != CallingConv::X86_StdCall && CC != CallingConv::X86_FastCall)
+    return;
+    
+  FMFInfoMap::const_iterator info_item = FunctionInfoMap.find(F);
+
+  const X86FunctionInfo *Info;
+  if (info_item == FunctionInfoMap.end()) {
+    // Calculate apropriate function info and populate map
+    FunctionInfoMap[F] = calculateFunctionInfo(F, TM.getTargetData());
+    Info = &FunctionInfoMap[F];
+  } else {
+    Info = &info_item->second;
+  }
+        
+  switch (Info->getDecorationStyle()) {
+  case None:
     break;
-  case X86Subtarget::isCygwin:
-    GlobalPrefix = "_";
-    COMMDirectiveTakesAlignment = false;
-    HasDotTypeDotSizeDirective = false;
+  case StdCall:
+    if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
+      Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
     break;
-  case X86Subtarget::isWindows:
-    GlobalPrefix = "_";
-    HasDotTypeDotSizeDirective = false;
+  case FastCall:
+    if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
+      Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
+
+    if (Name[0] == '_') {
+      Name[0] = '@';
+    } else {
+      Name = '@' + Name;
+    }    
     break;
-  default: break;
+  default:
+    assert(0 && "Unsupported DecorationStyle");
   }
-  
-  if (forDarwin) {
+}
+
+/// doInitialization
+bool X86SharedAsmPrinter::doInitialization(Module &M) {
+  if (Subtarget->isTargetELF() ||
+      Subtarget->isTargetCygMing() ||
+      Subtarget->isTargetDarwin()) {
     // Emit initial debug information.
     DW.BeginModule(&M);
   }
@@ -89,12 +118,16 @@ bool X86SharedAsmPrinter::doInitialization(Module &M) {
 }
 
 bool X86SharedAsmPrinter::doFinalization(Module &M) {
+  // Note: this code is not shared by the Intel printer as it is too different
+  // from how MASM does things.  When making changes here don't forget to look
+  // at X86IntelAsmPrinter::doFinalization().
   const TargetData *TD = TM.getTargetData();
-
+  
   // Print out module-level global variables here.
   for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
        I != E; ++I) {
-    if (!I->hasInitializer()) continue;   // External global require no code
+    if (!I->hasInitializer())
+      continue;   // External global require no code
     
     // Check to see if this is a special global used by LLVM, if so, emit it.
     if (EmitSpecialLLVMGlobal(I))
@@ -103,82 +136,162 @@ bool X86SharedAsmPrinter::doFinalization(Module &M) {
     std::string name = Mang->getValueName(I);
     Constant *C = I->getInitializer();
     unsigned Size = TD->getTypeSize(C->getType());
-    unsigned Align = getPreferredAlignmentLog(I);
+    unsigned Align = TD->getPreferredAlignmentLog(I);
 
     if (C->isNullValue() && /* FIXME: Verify correct */
+        !I->hasSection() &&
         (I->hasInternalLinkage() || I->hasWeakLinkage() ||
          I->hasLinkOnceLinkage() ||
-         (forDarwin && I->hasExternalLinkage() && !I->hasSection()))) {
+         (Subtarget->isTargetDarwin() && 
+          I->hasExternalLinkage()))) {
       if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
       if (I->hasExternalLinkage()) {
           O << "\t.globl\t" << name << "\n";
           O << "\t.zerofill __DATA__, __common, " << name << ", "
             << Size << ", " << Align;
       } else {
-        SwitchSection(".data", I);
-        if (LCOMMDirective != NULL) {
+        if (!NoZerosInBSS && TAI->getBSSSection())
+          SwitchToDataSection(TAI->getBSSSection(), I);
+        else
+          SwitchToDataSection(TAI->getDataSection(), I);
+        if (TAI->getLCOMMDirective() != NULL) {
           if (I->hasInternalLinkage()) {
-            O << LCOMMDirective << name << "," << Size;
-            if (forDarwin)
-              O << "," << (AlignmentIsInBytes ? (1 << Align) : Align);
+            O << TAI->getLCOMMDirective() << name << "," << Size;
+            if (Subtarget->isTargetDarwin())
+              O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
           } else
-            O << COMMDirective  << name << "," << Size;
+            O << TAI->getCOMMDirective()  << name << "," << Size;
         } else {
-          if (I->hasInternalLinkage())
-            O << "\t.local\t" << name << "\n";
-          O << COMMDirective  << name << "," << Size;
-          if (COMMDirectiveTakesAlignment)
-            O << "," << (AlignmentIsInBytes ? (1 << Align) : Align);
+          if (!Subtarget->isTargetCygMing()) {
+            if (I->hasInternalLinkage())
+              O << "\t.local\t" << name << "\n";
+          }
+          O << TAI->getCOMMDirective()  << name << "," << Size;
+          if (TAI->getCOMMDirectiveTakesAlignment())
+            O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
         }
       }
-      O << "\t\t" << CommentString << " " << I->getName() << "\n";
+      O << "\t\t" << TAI->getCommentString() << " " << I->getName() << "\n";
     } else {
       switch (I->getLinkage()) {
       case GlobalValue::LinkOnceLinkage:
       case GlobalValue::WeakLinkage:
-        if (forDarwin) {
+        if (Subtarget->isTargetDarwin()) {
           O << "\t.globl " << name << "\n"
             << "\t.weak_definition " << name << "\n";
-          SwitchSection(".section __DATA,__datacoal_nt,coalesced", I);
+          SwitchToDataSection(".section __DATA,__const_coal,coalesced", I);
+        } else if (Subtarget->isTargetCygMing()) {
+          std::string SectionName(".section\t.data$linkonce." +
+                                  name +
+                                  ",\"aw\"");
+          SwitchToDataSection(SectionName.c_str(), I);
+          O << "\t.globl " << name << "\n"
+            << "\t.linkonce same_size\n";
         } else {
-          O << "\t.section\t.llvm.linkonce.d." << name << ",\"aw\",@progbits\n";
+          std::string SectionName("\t.section\t.llvm.linkonce.d." +
+                                  name +
+                                  ",\"aw\",@progbits");
+          SwitchToDataSection(SectionName.c_str(), I);
           O << "\t.weak " << name << "\n";
         }
         break;
       case GlobalValue::AppendingLinkage:
         // FIXME: appending linkage variables should go into a section of
         // their name or something.  For now, just emit them as external.
+      case GlobalValue::DLLExportLinkage:
+        DLLExportedGVs.insert(Mang->makeNameProper(I->getName(),""));
+        // FALL THROUGH
       case GlobalValue::ExternalLinkage:
         // If external or appending, declare as a global symbol
         O << "\t.globl " << name << "\n";
         // FALL THROUGH
-      case GlobalValue::InternalLinkage:
-        SwitchSection(".data", I);
+      case GlobalValue::InternalLinkage: {
+        if (I->isConstant()) {
+          const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
+          if (TAI->getCStringSection() && CVA && CVA->isCString()) {
+            SwitchToDataSection(TAI->getCStringSection(), I);
+            break;
+          }
+        }
+        // FIXME: special handling for ".ctors" & ".dtors" sections
+        if (I->hasSection() &&
+            (I->getSection() == ".ctors" ||
+             I->getSection() == ".dtors")) {
+          std::string SectionName = ".section " + I->getSection();
+          
+          if (Subtarget->isTargetCygMing()) {
+            SectionName += ",\"aw\"";
+          } else {
+            assert(!Subtarget->isTargetDarwin());
+            SectionName += ",\"aw\",@progbits";
+          }
+
+          SwitchToDataSection(SectionName.c_str());
+        } else {
+          if (C->isNullValue() && !NoZerosInBSS && TAI->getBSSSection())
+            SwitchToDataSection(TAI->getBSSSection(), I);
+          else
+            SwitchToDataSection(TAI->getDataSection(), I);
+        }
+        
         break;
+      }
       default:
         assert(0 && "Unknown linkage type!");
       }
 
       EmitAlignment(Align, I);
-      O << name << ":\t\t\t\t" << CommentString << " " << I->getName()
+      O << name << ":\t\t\t\t" << TAI->getCommentString() << " " << I->getName()
         << "\n";
-      if (HasDotTypeDotSizeDirective)
+      if (TAI->hasDotTypeDotSizeDirective())
         O << "\t.size " << name << ", " << Size << "\n";
+      // If the initializer is a extern weak symbol, remember to emit the weak
+      // reference!
+      if (const GlobalValue *GV = dyn_cast<GlobalValue>(C))
+        if (GV->hasExternalWeakLinkage())
+          ExtWeakSymbols.insert(GV);
 
       EmitGlobalConstant(C);
       O << '\n';
     }
+    if (I->hasHiddenVisibility())
+      if (const char *Directive = TAI->getHiddenDirective())
+        O << Directive << name << "\n";
+    
+    if (Subtarget->isTargetELF())
+      O << "\t.type " << name << ",@object\n";
   }
   
-  if (forDarwin) {
-    SwitchSection("", 0);
+  // Output linker support code for dllexported globals
+  if (DLLExportedGVs.begin() != DLLExportedGVs.end()) {
+    SwitchToDataSection(".section .drectve");
+  }
+
+  for (std::set<std::string>::iterator i = DLLExportedGVs.begin(),
+         e = DLLExportedGVs.end();
+         i != e; ++i) {
+    O << "\t.ascii \" -export:" << *i << ",data\"\n";
+  }    
+
+  if (DLLExportedFns.begin() != DLLExportedFns.end()) {
+    SwitchToDataSection(".section .drectve");
+  }
+
+  for (std::set<std::string>::iterator i = DLLExportedFns.begin(),
+         e = DLLExportedFns.end();
+         i != e; ++i) {
+    O << "\t.ascii \" -export:" << *i << "\"\n";
+  }    
+
+  if (Subtarget->isTargetDarwin()) {
+    SwitchToDataSection("");
 
     // Output stubs for dynamically-linked functions
     unsigned j = 1;
     for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
          i != e; ++i, ++j) {
-      SwitchSection(".section __IMPORT,__jump_table,symbol_stubs,"
-                    "self_modifying_code+pure_instructions,5", 0);
+      SwitchToDataSection(".section __IMPORT,__jump_table,symbol_stubs,"
+                          "self_modifying_code+pure_instructions,5", 0);
       O << "L" << *i << "$stub:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       O << "\thlt ; hlt ; hlt ; hlt ; hlt\n";
@@ -188,7 +301,8 @@ bool X86SharedAsmPrinter::doFinalization(Module &M) {
 
     // Output stubs for external and common global variables.
     if (GVStubs.begin() != GVStubs.end())
-      SwitchSection(".section __IMPORT,__pointers,non_lazy_symbol_pointers", 0);
+      SwitchToDataSection(
+                    ".section __IMPORT,__pointers,non_lazy_symbol_pointers");
     for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
          i != e; ++i) {
       O << "L" << *i << "$non_lazy_ptr:\n";
@@ -196,7 +310,7 @@ bool X86SharedAsmPrinter::doFinalization(Module &M) {
       O << "\t.long\t0\n";
     }
 
-    // Emit initial debug information.
+    // Emit final debug information.
     DW.EndModule();
 
     // Funny Darwin hack: This flag tells the linker that no global symbols
@@ -205,6 +319,21 @@ bool X86SharedAsmPrinter::doFinalization(Module &M) {
     // linker can safely perform dead code stripping.  Since LLVM never
     // generates code that does this, it is always safe to set.
     O << "\t.subsections_via_symbols\n";
+  } else if (Subtarget->isTargetCygMing()) {
+    // Emit type information for external functions
+    for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
+         i != e; ++i) {
+      O << "\t.def\t " << *i
+        << ";\t.scl\t" << COFF::C_EXT
+        << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
+        << ";\t.endef\n";
+    }
+    
+    // Emit final debug information.
+    DW.EndModule();    
+  } else if (Subtarget->isTargetELF()) {
+    // Emit final debug information.
+    DW.EndModule();
   }
 
   AsmPrinter::doFinalization(M);
@@ -216,13 +345,12 @@ bool X86SharedAsmPrinter::doFinalization(Module &M) {
 /// machine description.
 ///
 FunctionPass *llvm::createX86CodePrinterPass(std::ostream &o,
-                                             X86TargetMachine &tm){
-  switch (AsmWriterFlavor) {
-  default:
-    assert(0 && "Unknown asm flavor!");
-  case intel:
-    return new X86IntelAsmPrinter(o, tm);
-  case att:
-    return new X86ATTAsmPrinter(o, tm);
+                                             X86TargetMachine &tm) {
+  const X86Subtarget *Subtarget = &tm.getSubtarget<X86Subtarget>();
+
+  if (Subtarget->isFlavorIntel()) {
+    return new X86IntelAsmPrinter(o, tm, tm.getTargetAsmInfo());
+  } else {
+    return new X86ATTAsmPrinter(o, tm, tm.getTargetAsmInfo());
   }
 }