[llvm] ab7a410 - AMDGPU: Fix using wrong instruction for FP conversion

[Matt Arsenault via llvm-commits]

Author: Matt Arsenault
Date: 2020-03-29T14:03:07-04:00
New Revision: ab7a41069ebf2f628913face89e6a0ecc0348f5d

URL: https://github.com/llvm/llvm-project/commit/ab7a41069ebf2f628913face89e6a0ecc0348f5d
DIFF: https://github.com/llvm/llvm-project/commit/ab7a41069ebf2f628913face89e6a0ecc0348f5d.diff

LOG: AMDGPU: Fix using wrong instruction for FP conversion

This was was never actually hit, but FTRUNC was clearly not the intent
here.

Added: 
    

Modified: 
    llvm/lib/Target/AMDGPU/SIISelLowering.cpp
    llvm/lib/Target/AMDGPU/SIISelLowering.h

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/AMDGPU/SIISelLowering.cpp b/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
index 0848d5ece2ce..4ff42769b470 100644
--- a/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/SIISelLowering.cpp
@@ -1439,7 +1439,7 @@ SDValue SITargetLowering::convertArgType(SelectionDAG &DAG, EVT VT, EVT MemVT,
   }
 
   if (MemVT.isFloatingPoint())
-    Val = getFPExtOrFPTrunc(DAG, Val, SL, VT);
+    Val = getFPExtOrFPRound(DAG, Val, SL, VT);
   else if (Signed)
     Val = DAG.getSExtOrTrunc(Val, SL, VT);
   else
@@ -4538,13 +4538,14 @@ SDValue SITargetLowering::LowerRETURNADDR(SDValue Op,
   return DAG.getCopyFromReg(DAG.getEntryNode(), DL, Reg, VT);
 }
 
-SDValue SITargetLowering::getFPExtOrFPTrunc(SelectionDAG &DAG,
+SDValue SITargetLowering::getFPExtOrFPRound(SelectionDAG &DAG,
                                             SDValue Op,
                                             const SDLoc &DL,
                                             EVT VT) const {
   return Op.getValueType().bitsLE(VT) ?
       DAG.getNode(ISD::FP_EXTEND, DL, VT, Op) :
-      DAG.getNode(ISD::FTRUNC, DL, VT, Op);
+    DAG.getNode(ISD::FP_ROUND, DL, VT, Op,
+                DAG.getTargetConstant(0, DL, MVT::i32));
 }
 
 SDValue SITargetLowering::lowerFP_ROUND(SDValue Op, SelectionDAG &DAG) const {

diff  --git a/llvm/lib/Target/AMDGPU/SIISelLowering.h b/llvm/lib/Target/AMDGPU/SIISelLowering.h
index a5d18f170e66..1e02fcdcedbf 100644
--- a/llvm/lib/Target/AMDGPU/SIISelLowering.h
+++ b/llvm/lib/Target/AMDGPU/SIISelLowering.h
@@ -107,7 +107,7 @@ class SITargetLowering final : public AMDGPUTargetLowering {
 
   /// Converts \p Op, which must be of floating point type, to the
   /// floating point type \p VT, by either extending or truncating it.
-  SDValue getFPExtOrFPTrunc(SelectionDAG &DAG,
+  SDValue getFPExtOrFPRound(SelectionDAG &DAG,
                             SDValue Op,
                             const SDLoc &DL,
                             EVT VT) const;