reland: [Demangle] make llvm::demangle take std::string_view rather than const std::string&

As suggested by @erichkeane in
https://reviews.llvm.org/D141451#inline-1429549

There's potential for a lot more cleanups around these APIs. This is
just a start.

Callers need to be more careful about sub-expressions producing strings
that don't outlast the expression using `llvm::demangle`. Add a
release note.

Differential Revision: https://reviews.llvm.org/D149104

1 files changed, 4 insertions, 5 deletions

diff --git a/clang/lib/CodeGen/CodeGenAction.cpp b/clang/lib/CodeGen/CodeGenAction.cpp
index 784ff77..b93477f 100644
--- a/clang/lib/CodeGen/CodeGenAction.cpp
+++ b/clang/lib/CodeGen/CodeGenAction.cpp
@@ -635,9 +635,8 @@ BackendConsumer::StackSizeDiagHandler(const llvm::DiagnosticInfoStackSize &D) {
     return false;
 
   Diags.Report(*Loc, diag::warn_fe_frame_larger_than)
-      << D.getStackSize()
-      << D.getStackLimit()
-      << llvm::demangle(D.getFunction().getName().str());
+      << D.getStackSize() << D.getStackLimit()
+      << llvm::demangle(D.getFunction().getName());
   return true;
 }
 
@@ -651,7 +650,7 @@ bool BackendConsumer::ResourceLimitDiagHandler(
 
   Diags.Report(*Loc, DiagID)
       << D.getResourceName() << D.getResourceSize() << D.getResourceLimit()
-      << llvm::demangle(D.getFunction().getName().str());
+      << llvm::demangle(D.getFunction().getName());
   return true;
 }
 
@@ -856,7 +855,7 @@ void BackendConsumer::DontCallDiagHandler(const DiagnosticInfoDontCall &D) {
   Diags.Report(LocCookie, D.getSeverity() == DiagnosticSeverity::DS_Error
                               ? diag::err_fe_backend_error_attr
                               : diag::warn_fe_backend_warning_attr)
-      << llvm::demangle(D.getFunctionName().str()) << D.getNote();
+      << llvm::demangle(D.getFunctionName()) << D.getNote();
 }
 
 void BackendConsumer::MisExpectDiagHandler(