commit 757d317c24288bdfb333b6b2c1fbd7ae01d59493
author Erich Keane <erich.keane@intel.com> Wed Nov 02 18:29:35 2016 +0000
committer Erich Keane <erich.keane@intel.com> Wed Nov 02 18:29:35 2016 +0000
tree 6bc5cdaab773009ff9f3b9b0ffaee356b82dc279
parent 1867c6cd422a18a6e93a8c851d86993671a1718b

regcall: Implement regcall Calling Conv in clang

This patch implements the register call calling convention, which ensures
as many values as possible are passed in registers. CodeGen changes
were committed in https://reviews.llvm.org/rL284108.

Differential Revision: https://reviews.llvm.org/D25204

llvm-svn: 285849

clang/lib/AST/ItaniumMangle.cpp

diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 7f362f6..3208e4e 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -493,6 +493,7 @@
   void mangleUnscopedTemplateName(TemplateName,
                                   const AbiTagList *AdditionalAbiTags);
   void mangleSourceName(const IdentifierInfo *II);
+  void mangleRegCallName(const IdentifierInfo *II);
   void mangleSourceNameWithAbiTags(
       const NamedDecl *ND, const AbiTagList *AdditionalAbiTags = nullptr);
   void mangleLocalName(const Decl *D,
@@ -1241,7 +1242,15 @@
           getEffectiveDeclContext(ND)->isFileContext())
         Out << 'L';
 
-      mangleSourceName(II);
+      auto *FD = dyn_cast<FunctionDecl>(ND);
+      bool IsRegCall = FD &&
+                       FD->getType()->castAs<FunctionType>()->getCallConv() ==
+                           clang::CC_X86RegCall;
+      if (IsRegCall)
+        mangleRegCallName(II);
+      else
+        mangleSourceName(II);
+
       writeAbiTags(ND, AdditionalAbiTags);
       break;
     }
@@ -1415,6 +1424,14 @@
   }
 }
 
+void CXXNameMangler::mangleRegCallName(const IdentifierInfo *II) {
+  // <source-name> ::= <positive length number> __regcall3__ <identifier>
+  // <number> ::= [n] <non-negative decimal integer>
+  // <identifier> ::= <unqualified source code identifier>
+  Out << II->getLength() + sizeof("__regcall3__") - 1 << "__regcall3__"
+      << II->getName();
+}
+
 void CXXNameMangler::mangleSourceName(const IdentifierInfo *II) {
   // <source-name> ::= <positive length number> <identifier>
   // <number> ::= [n] <non-negative decimal integer>
@@ -2497,6 +2514,7 @@
   case CC_X86Pascal:
   case CC_X86_64Win64:
   case CC_X86_64SysV:
+  case CC_X86RegCall:
   case CC_AAPCS:
   case CC_AAPCS_VFP:
   case CC_IntelOclBicc: