[ItaniumMangle] Refactor long double/__float128 mangling and fix the mangled code

In gcc PowerPC, long double has 3 mangling schemes:

-mlong-double-64: `e`
-mlong-double-128 -mabi=ibmlongdouble: `g`
-mlong-double-128 -mabi=ieeelongdouble: `u9__ieee128` (gcc <= 8.1: `U10__float128`)

The current useFloat128ManglingForLongDouble() bisection is not suitable
when we support -mlong-double-128 in clang (D64277). Replace
useFloat128ManglingForLongDouble() with getLongDoubleMangling() and
getFloat128Mangling() to allow 3 mangling schemes.

I also deleted the `getTriple().isOSBinFormatELF()` check (the Darwin
support has gone: https://reviews.llvm.org/D50988).

For x86, change the mangled code of __float128 from `U10__float128` to `g`. `U10__float128` was wrongly copied from PowerPC.
The test will be added to `test/CodeGen/x86-long-double.cpp` in D64277.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D64276

llvm-svn: 365480

1 files changed, 10 insertions, 21 deletions

diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 99556a6e70d..5f4644b0f7c 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -2608,30 +2608,19 @@ void CXXNameMangler::mangleType(const BuiltinType *T) {
     Out << 'd';
     break;
   case BuiltinType::LongDouble: {
-    bool UseFloat128Mangling =
-        getASTContext().getTargetInfo().useFloat128ManglingForLongDouble();
-    if (getASTContext().getLangOpts().OpenMP &&
-        getASTContext().getLangOpts().OpenMPIsDevice) {
-      UseFloat128Mangling = getASTContext()
-                                .getAuxTargetInfo()
-                                ->useFloat128ManglingForLongDouble();
-    }
-    Out << (UseFloat128Mangling ? 'g' : 'e');
+    const TargetInfo *TI = getASTContext().getLangOpts().OpenMP &&
+                                   getASTContext().getLangOpts().OpenMPIsDevice
+                               ? getASTContext().getAuxTargetInfo()
+                               : &getASTContext().getTargetInfo();
+    Out << TI->getLongDoubleMangling();
     break;
   }
   case BuiltinType::Float128: {
-    bool UseFloat128Mangling =
-        getASTContext().getTargetInfo().useFloat128ManglingForLongDouble();
-    if (getASTContext().getLangOpts().OpenMP &&
-        getASTContext().getLangOpts().OpenMPIsDevice) {
-      UseFloat128Mangling = getASTContext()
-                                .getAuxTargetInfo()
-                                ->useFloat128ManglingForLongDouble();
-    }
-    if (UseFloat128Mangling)
-      Out << "U10__float128"; // Match the GCC mangling
-    else
-      Out << 'g';
+    const TargetInfo *TI = getASTContext().getLangOpts().OpenMP &&
+                                   getASTContext().getLangOpts().OpenMPIsDevice
+                               ? getASTContext().getAuxTargetInfo()
+                               : &getASTContext().getTargetInfo();
+    Out << TI->getFloat128Mangling();
     break;
   }
   case BuiltinType::NullPtr: