[llvm] r281868 - [AVX-512] Don't lower CVTPD2PS intrinsics to ISD::FP_ROUND with an X86 rounding mode encoding in the second operand. This immediate should only be 0 or 1 and indicates if the truncation loses precision.

[Craig Topper via llvm-commits]

Author: ctopper
Date: Sun Sep 18 16:49:32 2016
New Revision: 281868

URL: http://llvm.org/viewvc/llvm-project?rev=281868&view=rev
Log:
[AVX-512] Don't lower CVTPD2PS intrinsics to ISD::FP_ROUND with an X86 rounding mode encoding in the second operand. This immediate should only be 0 or 1 and indicates if the truncation loses precision.

Also enhance an assert in SelectionDAG::getNode to flag this sort of problem in the future.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/lib/Target/X86/X86IntrinsicsInfo.h

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp?rev=281868&r1=281867&r2=281868&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp Sun Sep 18 16:49:32 2016
@@ -3603,7 +3603,8 @@ SDValue SelectionDAG::getNode(unsigned O
     assert(VT.isFloatingPoint() &&
            N1.getValueType().isFloatingPoint() &&
            VT.bitsLE(N1.getValueType()) &&
-           N2C && "Invalid FP_ROUND!");
+           N2C && (N2C->getZExtValue() == 0 || N2C->getZExtValue() == 1) &&
+           "Invalid FP_ROUND!");
     if (N1.getValueType() == VT) return N1;  // noop conversion.
     break;
   case ISD::AssertSext:

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=281868&r1=281867&r2=281868&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sun Sep 18 16:49:32 2016
@@ -17931,6 +17931,31 @@ static SDValue LowerINTRINSIC_WO_CHAIN(S
                                               Src1, Src2, Src3, Src4),
                                   Mask, PassThru, Subtarget, DAG);
     }
+    case CVTPD2PS: {
+      SDValue Src = Op.getOperand(1);
+      SDValue PassThru = Op.getOperand(2);
+      SDValue Mask = Op.getOperand(3);
+      // We add rounding mode to the Node when
+      //   - RM Opcode is specified and
+      //   - RM is not "current direction".
+      unsigned IntrWithRoundingModeOpcode = IntrData->Opc1;
+      if (IntrWithRoundingModeOpcode != 0) {
+        SDValue Rnd = Op.getOperand(4);
+        unsigned Round = cast<ConstantSDNode>(Rnd)->getZExtValue();
+        if (Round != X86::STATIC_ROUNDING::CUR_DIRECTION) {
+          return getVectorMaskingNode(DAG.getNode(IntrWithRoundingModeOpcode,
+                                      dl, Op.getValueType(),
+                                      Src, Rnd),
+                                      Mask, PassThru, Subtarget, DAG);
+        }
+      }
+      assert(IntrData->Opc0 == ISD::FP_ROUND && "Unexpected opcode!");
+      // ISD::FP_ROUND has a second argument that indicates if the truncation
+      // does not change the value. Set it to 0 since it can change.
+      return getVectorMaskingNode(DAG.getNode(IntrData->Opc0, dl, VT, Src,
+                                              DAG.getIntPtrConstant(0, dl)),
+                                  Mask, PassThru, Subtarget, DAG);
+    }
     case FPCLASS: {
       // FPclass intrinsics with mask
        SDValue Src1 = Op.getOperand(1);

Modified: llvm/trunk/lib/Target/X86/X86IntrinsicsInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86IntrinsicsInfo.h?rev=281868&r1=281867&r2=281868&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86IntrinsicsInfo.h (original)
+++ llvm/trunk/lib/Target/X86/X86IntrinsicsInfo.h Sun Sep 18 16:49:32 2016
@@ -23,7 +23,7 @@ enum IntrinsicType : uint16_t {
   INTR_NO_TYPE,
   GATHER, SCATTER, PREFETCH, RDSEED, RDRAND, RDPMC, RDTSC, XTEST, XGETBV, ADX, FPCLASS, FPCLASSS,
   INTR_TYPE_1OP, INTR_TYPE_2OP, INTR_TYPE_3OP, INTR_TYPE_4OP,
-  CMP_MASK, CMP_MASK_CC,CMP_MASK_SCALAR_CC, VSHIFT, COMI, COMI_RM,
+  CMP_MASK, CMP_MASK_CC,CMP_MASK_SCALAR_CC, VSHIFT, COMI, COMI_RM, CVTPD2PS,
   INTR_TYPE_1OP_MASK, INTR_TYPE_1OP_MASK_RM,
   INTR_TYPE_2OP_MASK, INTR_TYPE_2OP_MASK_RM, INTR_TYPE_2OP_IMM8_MASK,
   INTR_TYPE_3OP_MASK, INTR_TYPE_3OP_MASK_RM, INTR_TYPE_3OP_IMM8_MASK,
@@ -499,9 +499,9 @@ static const IntrinsicData  IntrinsicsWi
                     X86ISD::FP_TO_SINT_RND, X86ISD::FP_TO_SINT_RND),
   X86_INTRINSIC_DATA(avx512_mask_cvtpd2ps,     INTR_TYPE_1OP_MASK,
                     X86ISD::VFPROUND, 0),
-  X86_INTRINSIC_DATA(avx512_mask_cvtpd2ps_256, INTR_TYPE_1OP_MASK_RM,
+  X86_INTRINSIC_DATA(avx512_mask_cvtpd2ps_256, CVTPD2PS,
                      ISD::FP_ROUND, 0),
-  X86_INTRINSIC_DATA(avx512_mask_cvtpd2ps_512, INTR_TYPE_1OP_MASK_RM,
+  X86_INTRINSIC_DATA(avx512_mask_cvtpd2ps_512, CVTPD2PS,
                      ISD::FP_ROUND, X86ISD::VFPROUND),
   X86_INTRINSIC_DATA(avx512_mask_cvtpd2qq_128, INTR_TYPE_1OP_MASK,
                      X86ISD::FP_TO_SINT_RND, 0),