Refactor code to reduce indentation and improve readability. (NFC)

llvm-svn: 298665

1 files changed, 53 insertions, 43 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 40712463590..a550ff2fb90 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -145,59 +145,69 @@ DIE *DwarfCompileUnit::getOrCreateGlobalVariableDIE(
   for (const auto &GE : GlobalExprs) {
     const GlobalVariable *Global = GE.Var;
     const DIExpression *Expr = GE.Expr;
+
     // For compatibility with DWARF 3 and earlier,
     // DW_AT_location(DW_OP_constu, X, DW_OP_stack_value) becomes
     // DW_AT_const_value(X).
     if (GlobalExprs.size() == 1 && Expr && Expr->isConstant()) {
+      addToAccelTable = true;
       addConstantValue(*VariableDIE, /*Unsigned=*/true, Expr->getElement(1));
-      // We cannot describe the location of dllimport'd variables: the
-      // computation of their address requires loads from the IAT.
-    } else if ((Global && !Global->hasDLLImportStorageClass()) ||
-               (Expr && Expr->isConstant())) {
-      if (!Loc) {
-        Loc = new (DIEValueAllocator) DIELoc;
-        DwarfExpr = llvm::make_unique<DIEDwarfExpression>(*Asm, *this, *Loc);
-      }
+      break;
+    }
+
+    // We cannot describe the location of dllimport'd variables: the
+    // computation of their address requires loads from the IAT.
+    if (Global && Global->hasDLLImportStorageClass())
+      continue;
+
+    // Nothing to describe without address or constant.
+    if (!Global && (!Expr || !Expr->isConstant()))
+      continue;
+
+    if (!Loc) {
       addToAccelTable = true;
-      if (Global) {
-        const MCSymbol *Sym = Asm->getSymbol(Global);
-        if (Global->isThreadLocal()) {
-          if (Asm->TM.Options.EmulatedTLS) {
-            // TODO: add debug info for emulated thread local mode.
-          } else {
-            // FIXME: Make this work with -gsplit-dwarf.
-            unsigned PointerSize = Asm->getDataLayout().getPointerSize();
-            assert((PointerSize == 4 || PointerSize == 8) &&
-                   "Add support for other sizes if necessary");
-            // Based on GCC's support for TLS:
-            if (!DD->useSplitDwarf()) {
-              // 1) Start with a constNu of the appropriate pointer size
-              addUInt(*Loc, dwarf::DW_FORM_data1,
-                      PointerSize == 4 ? dwarf::DW_OP_const4u
-                                       : dwarf::DW_OP_const8u);
-              // 2) containing the (relocated) offset of the TLS variable
-              //    within the module's TLS block.
-              addExpr(*Loc, dwarf::DW_FORM_udata,
-                      Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
-            } else {
-              addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
-              addUInt(*Loc, dwarf::DW_FORM_udata,
-                      DD->getAddressPool().getIndex(Sym, /* TLS */ true));
-            }
-            // 3) followed by an OP to make the debugger do a TLS lookup.
+      Loc = new (DIEValueAllocator) DIELoc;
+      DwarfExpr = llvm::make_unique<DIEDwarfExpression>(*Asm, *this, *Loc);
+    }
+
+    if (Global) {
+      const MCSymbol *Sym = Asm->getSymbol(Global);
+      if (Global->isThreadLocal()) {
+        if (Asm->TM.Options.EmulatedTLS) {
+          // TODO: add debug info for emulated thread local mode.
+        } else {
+          // FIXME: Make this work with -gsplit-dwarf.
+          unsigned PointerSize = Asm->getDataLayout().getPointerSize();
+          assert((PointerSize == 4 || PointerSize == 8) &&
+                 "Add support for other sizes if necessary");
+          // Based on GCC's support for TLS:
+          if (!DD->useSplitDwarf()) {
+            // 1) Start with a constNu of the appropriate pointer size
             addUInt(*Loc, dwarf::DW_FORM_data1,
-                    DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
-                                          : dwarf::DW_OP_form_tls_address);
+                    PointerSize == 4 ? dwarf::DW_OP_const4u
+                                     : dwarf::DW_OP_const8u);
+            // 2) containing the (relocated) offset of the TLS variable
+            //    within the module's TLS block.
+            addExpr(*Loc, dwarf::DW_FORM_udata,
+                    Asm->getObjFileLowering().getDebugThreadLocalSymbol(Sym));
+          } else {
+            addUInt(*Loc, dwarf::DW_FORM_data1, dwarf::DW_OP_GNU_const_index);
+            addUInt(*Loc, dwarf::DW_FORM_udata,
+                    DD->getAddressPool().getIndex(Sym, /* TLS */ true));
           }
-        } else {
-          DD->addArangeLabel(SymbolCU(this, Sym));
-          addOpAddress(*Loc, Sym);
+          // 3) followed by an OP to make the debugger do a TLS lookup.
+          addUInt(*Loc, dwarf::DW_FORM_data1,
+                  DD->useGNUTLSOpcode() ? dwarf::DW_OP_GNU_push_tls_address
+                                        : dwarf::DW_OP_form_tls_address);
         }
+      } else {
+        DD->addArangeLabel(SymbolCU(this, Sym));
+        addOpAddress(*Loc, Sym);
       }
-      if (Expr) {
-        DwarfExpr->addFragmentOffset(Expr);
-        DwarfExpr->addExpression(Expr);
-      }
+    }
+    if (Expr) {
+      DwarfExpr->addFragmentOffset(Expr);
+      DwarfExpr->addExpression(Expr);
     }
   }
   if (Loc)