Fix FP_TO_UINT->i32 on ppc32 -mcpu=g5. This was

using Promote which won't work because i64 isn't
a legal type.  It's easy enough to use Custom, but
then we have the problem that when the type
legalizer is promoting FP_TO_UINT->i16, it has no
way of telling it should prefer FP_TO_SINT->i32
to FP_TO_UINT->i32.  I have uncomfortably hacked
this by making the type legalizer choose FP_TO_SINT
when both are Custom.
This fixes several regressions in the testsuite.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72891 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 6 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index eb9342cc8b..0d777bf798 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -356,13 +356,12 @@ SDValue DAGTypeLegalizer::PromoteIntRes_FP_TO_XINT(SDNode *N) {
   unsigned NewOpc = N->getOpcode();
   DebugLoc dl = N->getDebugLoc();
 
-  // If we're promoting a UINT to a larger size, check to see if the new node
-  // will be legal.  If it isn't, check to see if FP_TO_SINT is legal, since
-  // we can use that instead.  This allows us to generate better code for
-  // FP_TO_UINT for small destination sizes on targets where FP_TO_UINT is not
-  // legal, such as PowerPC.
+  // If we're promoting a UINT to a larger size and the larger FP_TO_UINT is
+  // not Legal, check to see if we can use FP_TO_SINT instead.  (If both UINT
+  // and SINT conversions are Custom, there is no way to tell which is preferable.
+  // We choose SINT because that's the right thing on PPC.)  
   if (N->getOpcode() == ISD::FP_TO_UINT &&
-      !TLI.isOperationLegalOrCustom(ISD::FP_TO_UINT, NVT) &&
+      !TLI.isOperationLegal(ISD::FP_TO_UINT, NVT) &&
       TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NVT))
     NewOpc = ISD::FP_TO_SINT;