From fea89c14ecf5e61c627942940fa5a9cde6b28a51 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Thu, 27 Apr 2006 08:40:39 +0000
Subject: [PATCH] Make x86 isel lowering produce tailcall nodes. They are match
 to normal calls for now.

Patch contributed by Alexander Friedman.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27994 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86ISelLowering.cpp |  2 +-
 lib/Target/X86/X86InstrInfo.td     | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index ccec18476fe..139fc95b672 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1203,7 +1203,7 @@ X86TargetLowering::LowerFastCCCallTo(SDOperand Chain, const Type *RetTy,
     Ops.push_back(InFlag);
 
   // FIXME: Do not generate X86ISD::TAILCALL for now.
-  Chain = DAG.getNode(X86ISD::CALL, NodeTys, Ops);
+  Chain = DAG.getNode(isTailCall ? X86ISD::TAILCALL : X86ISD::CALL, NodeTys, Ops);
   InFlag = Chain.getValue(1);
 
   NodeTys.clear();
diff --git a/lib/Target/X86/X86InstrInfo.td b/lib/Target/X86/X86InstrInfo.td
index 4ea13fe9b71..77c167242c3 100644
--- a/lib/Target/X86/X86InstrInfo.td
+++ b/lib/Target/X86/X86InstrInfo.td
@@ -75,6 +75,9 @@ def X86callseq_end :
 def X86call    : SDNode<"X86ISD::CALL",     SDT_X86Call,
                         [SDNPHasChain, SDNPOutFlag, SDNPOptInFlag]>;
 
+def X86tailcall    : SDNode<"X86ISD::TAILCALL",     SDT_X86Call,
+                        [SDNPHasChain, SDNPOutFlag, SDNPOptInFlag]>;
+
 def X86rep_stos: SDNode<"X86ISD::REP_STOS", SDTX86RepStr,
                         [SDNPHasChain, SDNPInFlag, SDNPOutFlag]>;
 def X86rep_movs: SDNode<"X86ISD::REP_MOVS", SDTX86RepStr,
@@ -2329,6 +2332,19 @@ def : Pat<(store (X86Wrapper texternalsym:$src), addr:$dst),
           (MOV32mi addr:$dst, texternalsym:$src)>;
 
 // Calls
+def : Pat<(X86tailcall R32:$dst),
+      (CALL32r     R32:$dst)>;
+
+def : Pat<(X86tailcall (loadi32 addr:$dst)),
+      (CALL32m addr:$dst)>;
+
+def : Pat<(X86tailcall tglobaladdr:$dst),
+          (CALLpcrel32 tglobaladdr:$dst)>;
+def : Pat<(X86tailcall texternalsym:$dst),
+          (CALLpcrel32 texternalsym:$dst)>;
+
+
+
 def : Pat<(X86call tglobaladdr:$dst),
           (CALLpcrel32 tglobaladdr:$dst)>;
 def : Pat<(X86call texternalsym:$dst),
-- 
2.34.1