Use DW_FORM_sdata for signed constant values and udata on occasion

when we can. Migrate from using blocks when we're adding just a
single attribute and floating point values are an unsigned, not signed,
bag of bits.

Update all test cases accordingly.

llvm-svn: 189419

1 files changed, 53 insertions, 22 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 8cef3e2b251..7b3842811a3 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -606,21 +606,36 @@ void CompileUnit::addConstantValue(DIE *Die, const MachineOperand &MO,
   // their maximum bit width which is a bit unfortunate (& doesn't prefer
   // udata/sdata over dataN as suggested by the DWARF spec)
   assert(MO.isImm() && "Invalid machine operand!");
-  DIEBlock *Block = new (DIEValueAllocator) DIEBlock();
   int SizeInBits = -1;
   bool SignedConstant = isTypeSigned(Ty, &SizeInBits);
-  uint16_t Form = SignedConstant ? dwarf::DW_FORM_sdata : dwarf::DW_FORM_udata;
-  switch (SizeInBits) {
-    case 8:  Form = dwarf::DW_FORM_data1; break;
-    case 16: Form = dwarf::DW_FORM_data2; break;
-    case 32: Form = dwarf::DW_FORM_data4; break;
-    case 64: Form = dwarf::DW_FORM_data8; break;
-    default: break;
+  uint16_t Form;
+
+  // If we're a signed constant definitely use sdata.
+  if (SignedConstant) {
+    addSInt(Die, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata, MO.getImm());
+    return;
   }
-  SignedConstant ? addSInt(Block, 0, Form, MO.getImm())
-    : addUInt(Block, 0, Form, MO.getImm());
 
-  addBlock(Die, dwarf::DW_AT_const_value, 0, Block);
+  // Else use data for now unless it's larger than we can deal with.
+  switch (SizeInBits) {
+  case 8:
+    Form = dwarf::DW_FORM_data1;
+    break;
+  case 16:
+    Form = dwarf::DW_FORM_data2;
+    break;
+  case 32:
+    Form = dwarf::DW_FORM_data4;
+    break;
+  case 64:
+    Form = dwarf::DW_FORM_data8;
+    break;
+  default:
+    Form = dwarf::DW_FORM_udata;
+    addUInt(Die, dwarf::DW_AT_const_value, Form, MO.getImm());
+    return;
+  }
+  addUInt(Die, dwarf::DW_AT_const_value, Form, MO.getImm());
 }
 
 /// addConstantFPValue - Add constant value entry in variable DIE.
@@ -649,7 +664,8 @@ void CompileUnit::addConstantFPValue(DIE *Die, const MachineOperand &MO) {
 
 /// addConstantFPValue - Add constant value entry in variable DIE.
 void CompileUnit::addConstantFPValue(DIE *Die, const ConstantFP *CFP) {
-  addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), false);
+  // Pass this down to addConstantValue as an unsigned bag of bits.
+  addConstantValue(Die, CFP->getValueAPF().bitcastToAPInt(), true);
 }
 
 /// addConstantValue - Add constant value entry in variable DIE.
@@ -662,19 +678,34 @@ void CompileUnit::addConstantValue(DIE *Die, const ConstantInt *CI,
 void CompileUnit::addConstantValue(DIE *Die, const APInt &Val, bool Unsigned) {
   unsigned CIBitWidth = Val.getBitWidth();
   if (CIBitWidth <= 64) {
-    unsigned form = 0;
+    // If we're a signed constant definitely use sdata.
+    if (!Unsigned) {
+      addSInt(Die, dwarf::DW_AT_const_value, dwarf::DW_FORM_sdata,
+              Val.getSExtValue());
+      return;
+    }
+
+    // Else use data for now unless it's larger than we can deal with.
+    uint16_t Form;
     switch (CIBitWidth) {
-    case 8: form = dwarf::DW_FORM_data1; break;
-    case 16: form = dwarf::DW_FORM_data2; break;
-    case 32: form = dwarf::DW_FORM_data4; break;
-    case 64: form = dwarf::DW_FORM_data8; break;
+    case 8:
+      Form = dwarf::DW_FORM_data1;
+      break;
+    case 16:
+      Form = dwarf::DW_FORM_data2;
+      break;
+    case 32:
+      Form = dwarf::DW_FORM_data4;
+      break;
+    case 64:
+      Form = dwarf::DW_FORM_data8;
+      break;
     default:
-      form = Unsigned ? dwarf::DW_FORM_udata : dwarf::DW_FORM_sdata;
+      addUInt(Die, dwarf::DW_AT_const_value, dwarf::DW_FORM_udata,
+              Val.getZExtValue());
+      return;
     }
-    if (Unsigned)
-      addUInt(Die, dwarf::DW_AT_const_value, form, Val.getZExtValue());
-    else
-      addSInt(Die, dwarf::DW_AT_const_value, form, Val.getSExtValue());
+    addUInt(Die, dwarf::DW_AT_const_value, Form, Val.getZExtValue());
     return;
   }