[llvm-commits] [llvm] r119738 - /llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp

[Bob Wilson]

Author: bwilson
Date: Thu Nov 18 15:16:28 2010
New Revision: 119738

URL: http://llvm.org/viewvc/llvm-project?rev=119738&view=rev
Log:
Split up ARM LowerShift function.
This function was being called from two different places for completely
unrelated reasons.  During type legalization, it was called to expand 64-bit
shift operations.  During operation legalization, it was called to handle
Neon vector shifts.  The vector shift code was not written to check for
illegal types, since it was assumed to be only called after type legalization.
Fixed this by splitting off the 64-bit shift expansion into a separate
function.  I don't have a particular testcase for this; I just noticed it
by inspection.

Modified:
    llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp?rev=119738&r1=119737&r2=119738&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMISelLowering.cpp Thu Nov 18 15:16:28 2010
@@ -2921,33 +2921,40 @@
   EVT VT = N->getValueType(0);
   DebugLoc dl = N->getDebugLoc();
 
+  if (!VT.isVector())
+    return SDValue();
+
   // Lower vector shifts on NEON to use VSHL.
-  if (VT.isVector()) {
-    assert(ST->hasNEON() && "unexpected vector shift");
+  assert(ST->hasNEON() && "unexpected vector shift");
 
-    // Left shifts translate directly to the vshiftu intrinsic.
-    if (N->getOpcode() == ISD::SHL)
-      return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, VT,
-                         DAG.getConstant(Intrinsic::arm_neon_vshiftu, MVT::i32),
-                         N->getOperand(0), N->getOperand(1));
-
-    assert((N->getOpcode() == ISD::SRA ||
-            N->getOpcode() == ISD::SRL) && "unexpected vector shift opcode");
-
-    // NEON uses the same intrinsics for both left and right shifts.  For
-    // right shifts, the shift amounts are negative, so negate the vector of
-    // shift amounts.
-    EVT ShiftVT = N->getOperand(1).getValueType();
-    SDValue NegatedCount = DAG.getNode(ISD::SUB, dl, ShiftVT,
-                                       getZeroVector(ShiftVT, DAG, dl),
-                                       N->getOperand(1));
-    Intrinsic::ID vshiftInt = (N->getOpcode() == ISD::SRA ?
-                               Intrinsic::arm_neon_vshifts :
-                               Intrinsic::arm_neon_vshiftu);
+  // Left shifts translate directly to the vshiftu intrinsic.
+  if (N->getOpcode() == ISD::SHL)
     return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, VT,
-                       DAG.getConstant(vshiftInt, MVT::i32),
-                       N->getOperand(0), NegatedCount);
-  }
+                       DAG.getConstant(Intrinsic::arm_neon_vshiftu, MVT::i32),
+                       N->getOperand(0), N->getOperand(1));
+
+  assert((N->getOpcode() == ISD::SRA ||
+          N->getOpcode() == ISD::SRL) && "unexpected vector shift opcode");
+
+  // NEON uses the same intrinsics for both left and right shifts.  For
+  // right shifts, the shift amounts are negative, so negate the vector of
+  // shift amounts.
+  EVT ShiftVT = N->getOperand(1).getValueType();
+  SDValue NegatedCount = DAG.getNode(ISD::SUB, dl, ShiftVT,
+                                     getZeroVector(ShiftVT, DAG, dl),
+                                     N->getOperand(1));
+  Intrinsic::ID vshiftInt = (N->getOpcode() == ISD::SRA ?
+                             Intrinsic::arm_neon_vshifts :
+                             Intrinsic::arm_neon_vshiftu);
+  return DAG.getNode(ISD::INTRINSIC_WO_CHAIN, dl, VT,
+                     DAG.getConstant(vshiftInt, MVT::i32),
+                     N->getOperand(0), NegatedCount);
+}
+
+static SDValue Expand64BitShift(SDNode *N, SelectionDAG &DAG,
+                                const ARMSubtarget *ST) {
+  EVT VT = N->getValueType(0);
+  DebugLoc dl = N->getDebugLoc();
 
   // We can get here for a node like i32 = ISD::SHL i32, i64
   if (VT != MVT::i64)
@@ -3958,7 +3965,7 @@
     break;
   case ISD::SRL:
   case ISD::SRA:
-    Res = LowerShift(N, DAG, Subtarget);
+    Res = Expand64BitShift(N, DAG, Subtarget);
     break;
   }
   if (Res.getNode())