8 files changed, 84 insertions, 8 deletions
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index 70eb3e1a82c..3350654daad 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -479,6 +479,7 @@ AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
   setTargetDAGCombine(ISD::FADD);
   setTargetDAGCombine(ISD::FSUB);
   setTargetDAGCombine(ISD::FNEG);
+  setTargetDAGCombine(ISD::FABS);
 }
 
 //===----------------------------------------------------------------------===//
@@ -2968,6 +2969,45 @@ SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
   }
+  case ISD::FP16_TO_FP: {
+    // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
+    // f16, but legalization of f16 fneg ends up pulling it out of the source.
+    // Put the fneg back as a legal source operation that can be matched later.
+    SDLoc SL(N);
+
+    SDValue Src = N0.getOperand(0);
+    EVT SrcVT = Src.getValueType();
+
+    // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
+    SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
+                                  DAG.getConstant(0x8000, SL, SrcVT));
+    return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
+  }
+  default:
+    return SDValue();
+  }
+}
+
+SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
+                                                 DAGCombinerInfo &DCI) const {
+  SelectionDAG &DAG = DCI.DAG;
+  SDValue N0 = N->getOperand(0);
+
+  if (!N0.hasOneUse())
+    return SDValue();
+
+  switch (N0.getOpcode()) {
+  case ISD::FP16_TO_FP: {
+    assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
+    SDLoc SL(N);
+    SDValue Src = N0.getOperand(0);
+    EVT SrcVT = Src.getValueType();
+
+    // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
+    SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
+                                  DAG.getConstant(0x7fff, SL, SrcVT));
+    return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
+  }
   default:
     return SDValue();
   }
@@ -3080,6 +3120,8 @@ SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
     return performSelectCombine(N, DCI);
   case ISD::FNEG:
     return performFNegCombine(N, DCI);
+  case ISD::FABS:
+    return performFAbsCombine(N, DCI);
   case AMDGPUISD::BFE_I32:
   case AMDGPUISD::BFE_U32: {
     assert(!N->getValueType(0).isVector() &&
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
index 880d571078b..58ac09f2698 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
@@ -85,6 +85,7 @@ protected:
                              SDValue RHS, DAGCombinerInfo &DCI) const;
   SDValue performSelectCombine(SDNode *N, DAGCombinerInfo &DCI) const;
   SDValue performFNegCombine(SDNode *N, DAGCombinerInfo &DCI) const;
+  SDValue performFAbsCombine(SDNode *N, DAGCombinerInfo &DCI) const;
 
   static EVT getEquivalentMemType(LLVMContext &Context, EVT VT);
 
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUInstructions.td b/llvm/lib/Target/AMDGPU/AMDGPUInstructions.td
index 004b10f5d20..7d2a52bccc8 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUInstructions.td
+++ b/llvm/lib/Target/AMDGPU/AMDGPUInstructions.td
@@ -637,6 +637,9 @@ def umax_oneuse : HasOneUseBinOp<umax>;
 def umin_oneuse : HasOneUseBinOp<umin>;
 def fminnum_oneuse : HasOneUseBinOp<fminnum>;
 def fmaxnum_oneuse : HasOneUseBinOp<fmaxnum>;
+def and_oneuse : HasOneUseBinOp<and>;
+def or_oneuse : HasOneUseBinOp<or>;
+def xor_oneuse : HasOneUseBinOp<xor>;
 } // Properties = [SDNPCommutative, SDNPAssociative]
 
 def sub_oneuse : HasOneUseBinOp<sub>;
diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/SIMCCodeEmitter.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/SIMCCodeEmitter.cpp
index 0c5bb0648a1..bdaa5aef83d 100644
--- a/llvm/lib/Target/AMDGPU/MCTargetDesc/SIMCCodeEmitter.cpp
+++ b/llvm/lib/Target/AMDGPU/MCTargetDesc/SIMCCodeEmitter.cpp
@@ -226,6 +226,8 @@ uint32_t SIMCCodeEmitter::getLitEncoding(const MCOperand &MO,
   case 8:
     return getLit64Encoding(static_cast<uint64_t>(Imm), STI);
   case 2:
+    // FIXME Is this correct? What do inline immediates do on SI for f16 src
+    // which does not have f16 support?
     return getLit16Encoding(static_cast<uint16_t>(Imm), STI);
   default:
     llvm_unreachable("invalid operand size");
diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
index e718b459ec3..51006589b5c 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
@@ -1824,7 +1824,8 @@ bool SIInstrInfo::isInlineConstant(const APInt &Imm) const {
     return AMDGPU::isInlinableLiteral64(Imm.getSExtValue(),
                                         ST.hasInv2PiInlineImm());
   case 16:
-    return AMDGPU::isInlinableLiteral16(Imm.getSExtValue(),
+    return ST.has16BitInsts() &&
+           AMDGPU::isInlinableLiteral16(Imm.getSExtValue(),
                                         ST.hasInv2PiInlineImm());
   default:
     llvm_unreachable("invalid bitwidth");
@@ -1854,8 +1855,13 @@ bool SIInstrInfo::isInlineConstant(const MachineOperand &MO,
   }
   case 16: {
     if (isInt<16>(Imm) || isUInt<16>(Imm)) {
+      // A few special case instructions have 16-bit operands on subtargets
+      // where 16-bit instructions are not legal.
+      // TODO: Do the 32-bit immediates work? We shouldn't really need to handle
+      // constants in these cases
       int16_t Trunc = static_cast<int16_t>(Imm);
-      return AMDGPU::isInlinableLiteral16(Trunc, ST.hasInv2PiInlineImm());
+      return ST.has16BitInsts() &&
+             AMDGPU::isInlinableLiteral16(Trunc, ST.hasInv2PiInlineImm());
     }
 
     return false;
diff --git a/llvm/lib/Target/AMDGPU/SIInstrInfo.td b/llvm/lib/Target/AMDGPU/SIInstrInfo.td
index cf9b9c5a145..a691ef11a86 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrInfo.td
+++ b/llvm/lib/Target/AMDGPU/SIInstrInfo.td
@@ -619,6 +619,8 @@ def SIOperand {
 def SRCMODS {
   int NONE = 0;
   int NEG = 1;
+  int ABS = 2;
+  int NEG_ABS = 3;
 }
 
 def DSTCLAMP {
@@ -1132,6 +1134,8 @@ def VOP_F64_I32 : VOPProfile <[f64, i32, untyped, untyped]>;
 def VOP_I32_F32 : VOPProfile <[i32, f32, untyped, untyped]>;
 def VOP_I32_F64 : VOPProfile <[i32, f64, untyped, untyped]>;
 def VOP_I32_I32 : VOPProfile <[i32, i32, untyped, untyped]>;
+def VOP_F16_F32 : VOPProfile <[f16, f32, untyped, untyped]>;
+def VOP_F32_F16 : VOPProfile <[f32, f16, untyped, untyped]>;
 
 def VOP_F32_F32_F16 : VOPProfile <[f32, f32, f16, untyped]>;
 def VOP_F32_F32_F32 : VOPProfile <[f32, f32, f32, untyped]>;
diff --git a/llvm/lib/Target/AMDGPU/SIInstructions.td b/llvm/lib/Target/AMDGPU/SIInstructions.td
index 5cdd139a83f..ed0609da9be 100644
--- a/llvm/lib/Target/AMDGPU/SIInstructions.td
+++ b/llvm/lib/Target/AMDGPU/SIInstructions.td
@@ -430,9 +430,26 @@ def : Pat <
 
 } // End Predicates = [UnsafeFPMath]
 
+
+// f16_to_fp patterns
+def : Pat <
+  (f32 (f16_to_fp i32:$src0)),
+  (V_CVT_F32_F16_e64 SRCMODS.NONE, $src0, DSTCLAMP.NONE, DSTOMOD.NONE)
+>;
+
+def : Pat <
+  (f32 (f16_to_fp (and_oneuse i32:$src0, 0x7fff))),
+  (V_CVT_F32_F16_e64 SRCMODS.ABS, $src0, DSTCLAMP.NONE, DSTOMOD.NONE)
+>;
+
+def : Pat <
+  (f32 (f16_to_fp (or_oneuse i32:$src0, 0x8000))),
+  (V_CVT_F32_F16_e64 SRCMODS.NEG_ABS, $src0, DSTCLAMP.NONE, DSTOMOD.NONE)
+>;
+
 def : Pat <
-  (f32 (fpextend f16:$src)),
-  (V_CVT_F32_F16_e32 $src)
+  (f32 (f16_to_fp (xor_oneuse i32:$src0, 0x8000))),
+  (V_CVT_F32_F16_e64 SRCMODS.NEG, $src0, DSTCLAMP.NONE, DSTOMOD.NONE)
 >;
 
 def : Pat <
@@ -440,9 +457,10 @@ def : Pat <
   (V_CVT_F64_F32_e32 (V_CVT_F32_F16_e32 $src))
 >;
 
+// fp_to_fp16 patterns
 def : Pat <
-  (f16 (fpround f32:$src)),
-  (V_CVT_F16_F32_e32 $src)
+  (i32 (fp_to_f16 (f32 (VOP3Mods0 f32:$src0, i32:$src0_modifiers, i1:$clamp, i32:$omod)))),
+  (V_CVT_F16_F32_e64 $src0_modifiers, f32:$src0, $clamp, $omod)
 >;
 
 def : Pat <
diff --git a/llvm/lib/Target/AMDGPU/VOP1Instructions.td b/llvm/lib/Target/AMDGPU/VOP1Instructions.td
index a15b9ceff2f..15abed4a76b 100644
--- a/llvm/lib/Target/AMDGPU/VOP1Instructions.td
+++ b/llvm/lib/Target/AMDGPU/VOP1Instructions.td
@@ -147,8 +147,8 @@ defm V_CVT_F32_I32 : VOP1Inst <"v_cvt_f32_i32", VOP_F32_I32, sint_to_fp>;
 defm V_CVT_F32_U32 : VOP1Inst <"v_cvt_f32_u32", VOP_F32_I32, uint_to_fp>;
 defm V_CVT_U32_F32 : VOP1Inst <"v_cvt_u32_f32", VOP_I32_F32, fp_to_uint>;
 defm V_CVT_I32_F32 : VOP1Inst <"v_cvt_i32_f32", VOP_I32_F32, fp_to_sint>;
-defm V_CVT_F16_F32 : VOP1Inst <"v_cvt_f16_f32", VOP_I32_F32, fp_to_f16>;
-defm V_CVT_F32_F16 : VOP1Inst <"v_cvt_f32_f16", VOP_F32_I32, f16_to_fp>;
+defm V_CVT_F16_F32 : VOP1Inst <"v_cvt_f16_f32", VOP_F16_F32, fpround>;
+defm V_CVT_F32_F16 : VOP1Inst <"v_cvt_f32_f16", VOP_F32_F16, fpextend>;
 defm V_CVT_RPI_I32_F32 : VOP1Inst <"v_cvt_rpi_i32_f32", VOP_I32_F32, cvt_rpi_i32_f32>;
 defm V_CVT_FLR_I32_F32 : VOP1Inst <"v_cvt_flr_i32_f32", VOP_I32_F32, cvt_flr_i32_f32>;
 defm V_CVT_OFF_F32_I4 : VOP1Inst  <"v_cvt_off_f32_i4", VOP_F32_I32>;