commit e637cbe4e40ef892c378801d95993be39193bb7e
author Richard Smith <richard-llvm@metafoo.co.uk> Tue May 21 23:15:18 2019 +0000
committer Richard Smith <richard-llvm@metafoo.co.uk> Tue May 21 23:15:18 2019 +0000
tree 96c64300984bc9620fc39b25a9a868b427866456
parent a49496fb2a16b729f6f6ec8b9a1e8c72133ac9d9

Refactor: split Uninitialized state on APValue into an "Absent" state
representing no such object, and an "Indeterminate" state representing
an uninitialized object. The latter is not yet used, but soon will be.

llvm-svn: 361328

clang/lib/CodeGen/CGExprConstant.cpp

diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 70904b1..caa327c 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -1860,8 +1860,10 @@
 llvm::Constant *ConstantEmitter::tryEmitPrivate(const APValue &Value,
                                                 QualType DestType) {
   switch (Value.getKind()) {
-  case APValue::Uninitialized:
-    llvm_unreachable("Constant expressions should be initialized.");
+  case APValue::None:
+  case APValue::Indeterminate:
+    // Out-of-lifetime and indeterminate values can be modeled as 'undef'.
+    return llvm::UndefValue::get(CGM.getTypes().ConvertType(DestType));
   case APValue::LValue:
     return ConstantLValueEmitter(*this, Value, DestType).tryEmit();
   case APValue::Int:

clang/lib/CodeGen/CodeGenFunction.cpp

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index a2d6d59..b9573f7 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -1990,7 +1990,7 @@
 
 void CodeGenFunction::EmitDeclRefExprDbgValue(const DeclRefExpr *E,
                                               const APValue &Init) {
-  assert(!Init.isUninit() && "Invalid DeclRefExpr initializer!");
+  assert(Init.hasValue() && "Invalid DeclRefExpr initializer!");
   if (CGDebugInfo *Dbg = getDebugInfo())
     if (CGM.getCodeGenOpts().getDebugInfo() >= codegenoptions::LimitedDebugInfo)
       Dbg->EmitGlobalVariable(E->getDecl(), Init);

clang/lib/CodeGen/CodeGenModule.cpp

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index a16e7ce..6daea41 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -4886,7 +4886,7 @@
     // evaluating the initializer if the surrounding constant expression
     // modifies the temporary.
     Value = getContext().getMaterializedTemporaryValue(E, false);
-    if (Value && Value->isUninit())
+    if (Value && Value->isAbsent())
       Value = nullptr;
   }