From e76ad6de40b5e4c0399257b0438914c8c85ceaa1 Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Fri, 28 Jan 2005 22:52:50 +0000
Subject: [PATCH] implement legalization of truncates whose results and sources
 need to be truncated, e.g. (truncate:i8 something:i16) on a 32 or 64-bit
 RISC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19879 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 32cf5970726..e435bd609de 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1035,10 +1035,13 @@ SDOperand SelectionDAGLegalize::PromoteOp(SDOperand Op) {
       if (Result.getValueType() > NVT)    // Truncate to NVT instead of VT
         Result = DAG.getNode(ISD::TRUNCATE, NVT, Result);
       break;
+    case Promote:
+      // The truncation is not required, because we don't guarantee anything
+      // about high bits anyway.
+      Result = PromoteOp(Node->getOperand(0));
+      break;
     case Expand:
       assert(0 && "Cannot handle expand yet");
-    case Promote:
-      assert(0 && "Cannot handle promote-promote yet");
     }
     break;
   case ISD::SIGN_EXTEND: