Output correct exception handling and frame info

on x86-64 linux.  This causes no regressions on
32 bit linux and 32 bit ppc.  More tests pass
on 64 bit ppc with no regressions.  I didn't
turn on eh on 64 bit linux because the intrinsics
needed to compile the eh runtime aren't done
yet.  But if you turn it on and link with the
mainline runtime then eh seems to work fine
on x86-64 linux with this patch.  Thanks to
Dale for testing.  The main point of the patch
is that if you output that some object is
encoded using 4 bytes you had better not output
8 bytes for it: the patch makes everything
consistent.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50825 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Target/TargetAsmInfo.h

@@ -339,10 +339,6 @@ namespace llvm {
     /// handle a weak_definition of constant 0 for an omitted EH frame.
     bool SupportsWeakOmittedEHFrame;  // Defaults to true.
 
-    /// ShortenEHDataON64Bit - True if target exception table format requires
-    /// 32-bit data in certain places even when targeting 64-bits.
-    bool ShortenEHDataOn64Bit;    // Defaults to false.
-
     /// DwarfSectionOffsetDirective - Special section offset directive.
     const char* DwarfSectionOffsetDirective; // Defaults to NULL
     
@@ -635,9 +631,6 @@ namespace llvm {
     bool getSupportsWeakOmittedEHFrame() const {
       return SupportsWeakOmittedEHFrame;
     }
-    bool getShortenEHDataOn64Bit() const {
-      return ShortenEHDataOn64Bit;
-    }
     const char *getDwarfSectionOffsetDirective() const {
       return DwarfSectionOffsetDirective;
     }    

lib/CodeGen/DwarfWriter.cpp

@@ -2796,7 +2796,7 @@ private:
   /// shouldEmitFrameModule - Per-module flag to indicate if frame moves 
   /// should be emitted.
   bool shouldEmitMovesModule;
-  
+
   /// EmitCommonEHFrame - Emit the common eh unwind frame.
   ///
   void EmitCommonEHFrame(const Function *Personality, unsigned Index) {
@@ -2813,7 +2813,7 @@ private:
 
     // Define base labels.
     EmitLabel("eh_frame_common", Index);
-    
+
     // Define the eh frame length.
     EmitDifference("eh_frame_common_end", Index,
                    "eh_frame_common_begin", Index, true);
@@ -2825,50 +2825,49 @@ private:
     Asm->EOL("CIE Identifier Tag");
     Asm->EmitInt8(DW_CIE_VERSION);
     Asm->EOL("CIE Version");
-    
+
     // The personality presence indicates that language specific information
     // will show up in the eh frame.
     Asm->EmitString(Personality ? "zPLR" : "zR");
     Asm->EOL("CIE Augmentation");
-    
+
     // Round out reader.
     Asm->EmitULEB128Bytes(1);
     Asm->EOL("CIE Code Alignment Factor");
     Asm->EmitSLEB128Bytes(stackGrowth);
-    Asm->EOL("CIE Data Alignment Factor");   
+    Asm->EOL("CIE Data Alignment Factor");
     Asm->EmitInt8(RI->getDwarfRegNum(RI->getRARegister(), true));
-    Asm->EOL("CIE RA Column");
+    Asm->EOL("CIE Return Address Column");
-    
+
     // If there is a personality, we need to indicate the functions location.
     if (Personality) {
       Asm->EmitULEB128Bytes(7);
       Asm->EOL("Augmentation Size");
 
-      if (TAI->getNeedsIndirectEncoding())
+      if (TAI->getNeedsIndirectEncoding()) {
         Asm->EmitInt8(DW_EH_PE_pcrel | DW_EH_PE_sdata4 | DW_EH_PE_indirect);
-      else
+        Asm->EOL("Personality (pcrel sdata4 indirect)");
+      } else {
         Asm->EmitInt8(DW_EH_PE_pcrel | DW_EH_PE_sdata4);
+        Asm->EOL("Personality (pcrel sdata4)");
+      }
 
-      Asm->EOL("Personality (pcrel sdata4 indirect)");
+      PrintRelDirective(true);
-      
-      PrintRelDirective(TAI->getShortenEHDataOn64Bit());
       O << TAI->getPersonalityPrefix();
       Asm->EmitExternalGlobal((const GlobalVariable *)(Personality));
       O << TAI->getPersonalitySuffix();
-      if (!TAI->getShortenEHDataOn64Bit()) {
+      O << "-" << TAI->getPCSymbol();
-        O << "-" << TAI->getPCSymbol();
-      }
       Asm->EOL("Personality");
 
-      Asm->EmitULEB128Bytes(DW_EH_PE_pcrel);
+      Asm->EmitInt8(DW_EH_PE_pcrel | DW_EH_PE_sdata4);
-      Asm->EOL("LSDA Encoding (pcrel)");
+      Asm->EOL("LSDA Encoding (pcrel sdata4)");
-      Asm->EmitULEB128Bytes(DW_EH_PE_pcrel);
+      Asm->EmitInt8(DW_EH_PE_pcrel | DW_EH_PE_sdata4);
-      Asm->EOL("FDE Encoding (pcrel)");
+      Asm->EOL("FDE Encoding (pcrel sdata4)");
    } else {
       Asm->EmitULEB128Bytes(1);
       Asm->EOL("Augmentation Size");
-      Asm->EmitULEB128Bytes(DW_EH_PE_pcrel);
+      Asm->EmitInt8(DW_EH_PE_pcrel | DW_EH_PE_sdata4);
-      Asm->EOL("FDE Encoding (pcrel)");
+      Asm->EOL("FDE Encoding (pcrel sdata4)");
     }
 
     // Indicate locations of general callee saved registers in frame.
@@ -2882,10 +2881,10 @@ private:
     Asm->EmitAlignment(TD->getPointerSize() == sizeof(int32_t) ? 2 : 3, 
                        0, 0, false);
     EmitLabel("eh_frame_common_end", Index);
-    
+
     Asm->EOL();
   }
-  
+
   /// EmitEHFrame - Emit function exception frame information.
   ///
   void EmitEHFrame(const FunctionEHFrameInfo &EHFrameInfo) {
@@ -2940,31 +2939,28 @@ private:
                         true, true, false);
       Asm->EOL("FDE CIE offset");
 
-      EmitReference("eh_func_begin", EHFrameInfo.Number, true);
+      EmitReference("eh_func_begin", EHFrameInfo.Number, true, true);
       Asm->EOL("FDE initial location");
       EmitDifference("eh_func_end", EHFrameInfo.Number,
-                     "eh_func_begin", EHFrameInfo.Number);
+                     "eh_func_begin", EHFrameInfo.Number, true);
       Asm->EOL("FDE address range");
-      
+
       // If there is a personality and landing pads then point to the language
       // specific data area in the exception table.
       if (EHFrameInfo.PersonalityIndex) {
-        Asm->EmitULEB128Bytes(TAI->getShortenEHDataOn64Bit() ? 8 : 4);
+        Asm->EmitULEB128Bytes(4);
         Asm->EOL("Augmentation size");
-        
+
-        if (EHFrameInfo.hasLandingPads) {
+        if (EHFrameInfo.hasLandingPads)
-          EmitReference("exception", EHFrameInfo.Number, true);
+          EmitReference("exception", EHFrameInfo.Number, true, true);
-        } else if (TD->getPointerSize() == 8) {
+        else
-          Asm->EmitInt64((int)0);
-        } else {
           Asm->EmitInt32((int)0);
-        }
         Asm->EOL("Language Specific Data Area");
       } else {
         Asm->EmitULEB128Bytes(0);
         Asm->EOL("Augmentation size");
       }
-      
+
       // Indicate locations of function specific  callee saved registers in
       // frame.
       EmitFrameMoves("eh_func_begin", EHFrameInfo.Number, EHFrameInfo.Moves, true);
@@ -3267,13 +3263,20 @@ private:
     }
 
     // Final tallies.
-    unsigned SizeSites = CallSites.size() * (sizeof(int32_t) + // Site start.
+
-                                             sizeof(int32_t) + // Site length.
+    // Call sites.
-                                             sizeof(int32_t)); // Landing pad.
+    const unsigned SiteStartSize  = sizeof(int32_t); // DW_EH_PE_udata4
+    const unsigned SiteLengthSize = sizeof(int32_t); // DW_EH_PE_udata4
+    const unsigned LandingPadSize = sizeof(int32_t); // DW_EH_PE_udata4
+    unsigned SizeSites = CallSites.size() * (SiteStartSize +
+                                             SiteLengthSize +
+                                             LandingPadSize);
     for (unsigned i = 0, e = CallSites.size(); i < e; ++i)
       SizeSites += Asm->SizeULEB128(CallSites[i].Action);
 
-    unsigned SizeTypes = TypeInfos.size() * TD->getPointerSize();
+    // Type infos.
+    const unsigned TypeInfoSize = TD->getPointerSize(); // DW_EH_PE_absptr
+    unsigned SizeTypes = TypeInfos.size() * TypeInfoSize;
 
     unsigned TypeOffset = sizeof(int8_t) + // Call site format
                           Asm->SizeULEB128(SizeSites) + // Call-site table length
@@ -3323,27 +3326,22 @@ private:
       }
 
       EmitSectionOffset(BeginTag, "eh_func_begin", BeginNumber, SubprogramCount,
-                        TAI->getShortenEHDataOn64Bit(), true);
+                        true, true);
       Asm->EOL("Region start");
 
       if (!S.EndLabel) {
         EmitDifference("eh_func_end", SubprogramCount, BeginTag, BeginNumber,
-                       TAI->getShortenEHDataOn64Bit());
+                       true);
       } else {
-        EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, 
+        EmitDifference("label", S.EndLabel, BeginTag, BeginNumber, true);
-                       TAI->getShortenEHDataOn64Bit());
       }
       Asm->EOL("Region length");
 
-      if (!S.PadLabel) {
+      if (!S.PadLabel)
-        if (TD->getPointerSize() == sizeof(int32_t) || TAI->getShortenEHDataOn64Bit())
+        Asm->EmitInt32(0);
-          Asm->EmitInt32(0);
+      else
-        else
-          Asm->EmitInt64(0);
-      } else {
         EmitSectionOffset("label", "eh_func_begin", S.PadLabel, SubprogramCount,
-                          TAI->getShortenEHDataOn64Bit(), true);
+                          true, true);
-      }
       Asm->EOL("Landing pad");
 
       Asm->EmitULEB128Bytes(S.Action);

lib/Target/TargetAsmInfo.cpp

@@ -90,7 +90,6 @@ TargetAsmInfo::TargetAsmInfo() :
   DwarfRequiresFrameSection(true),
   GlobalEHDirective(0),
   SupportsWeakOmittedEHFrame(true),
-  ShortenEHDataOn64Bit(false),
   DwarfSectionOffsetDirective(0),
   DwarfAbbrevSection(".debug_abbrev"),
   DwarfInfoSection(".debug_info"),

lib/Target/X86/X86TargetAsmInfo.cpp

@@ -120,8 +120,6 @@ X86TargetAsmInfo::X86TargetAsmInfo(const X86TargetMachine &TM) {
     GlobalEHDirective = "\t.globl\t";
     SupportsWeakOmittedEHFrame = false;
     AbsoluteEHSectionOffsets = false;
-    if (Subtarget->is64Bit())
-      ShortenEHDataOn64Bit = true;
     DwarfEHFrameSection =
     ".section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support";
     DwarfExceptionSection = ".section __DATA,__gcc_except_tab";