[DPWBS-1388] Add legality rules for G_INTRINSIC_TRUNC

llvm/lib/Target/TriCore/TriCoreLegalizerInfo.cpp

@@ -310,6 +310,10 @@ TriCoreLegalizerInfo::TriCoreLegalizerInfo(const TriCoreSubtarget &ST) {
       .clampScalar(0, s32, s64)
       .widenScalarToNextPow2(0);
 
+  // G_INTRINSIC_TRUNC should use custom legalization since we cannot model all
+  // semantics of this instruction on TriCore yet
+  getActionDefinitionsBuilder(G_INTRINSIC_TRUNC).customFor({s32, s64});
+
   // Floating Point Unary Ops
 
   // G_FPTOSI and G_FPTOUI are always legal for f32->s32 conversions.
@@ -529,6 +533,8 @@ bool TriCoreLegalizerInfo::legalizeCustom(MachineInstr &MI,
     return false;
   case TargetOpcode::G_FCMP:
     return legalizeFCmp(MI, MRI, MIRBuilder);
+  case TargetOpcode::G_INTRINSIC_TRUNC:
+    return legalizeIntrinsicTrunc(MI, MRI, MIRBuilder);
   case TargetOpcode::G_VAARG:
     return legalizeVaArg(MI, MRI, MIRBuilder);
   }
@@ -553,6 +559,38 @@ bool TriCoreLegalizerInfo::legalizeIntrinsic(
   return true;
 }
 
+bool TriCoreLegalizerInfo::legalizeIntrinsicTrunc(
+    MachineInstr &MI, MachineRegisterInfo &MRI,
+    MachineIRBuilder &MIRBuilder) const {
+  // Since G_INTRINSIC_TRUNC cannot be modeled in hardware, and because a
+  // libcall action is not supported, we need to create a libcall here
+  assert(MI.getOpcode() == TargetOpcode::G_INTRINSIC_TRUNC);
+
+  const Register DstReg = MI.getOperand(0).getReg();
+  const Register SrcReg = MI.getOperand(1).getReg();
+
+  LLVMContext &Ctx = MIRBuilder.getMF().getFunction().getContext();
+
+  const LLT SrcTy = MRI.getType(SrcReg);
+  const unsigned Size = SrcTy.getSizeInBits();
+
+  RTLIB::Libcall RTLibOpc = Size == 32 ? RTLIB::TRUNC_F32 : RTLIB::TRUNC_F64;
+  const auto Type = Size == 32 ? Type::getFloatTy(Ctx) : Type::getDoubleTy(Ctx);
+
+  MIRBuilder.setInstr(MI);
+
+  assert(SrcTy == MRI.getType(DstReg) &&
+         (SrcTy == LLT::scalar(32) || SrcTy == LLT::scalar(64)) &&
+         "Expected float or double float types");
+
+  if (createLibcall(MIRBuilder, RTLibOpc, {DstReg, Type}, {{SrcReg, Type}}) ==
+      LegalizerHelper::UnableToLegalize)
+    return false;
+
+  MI.eraseFromParent();
+  return true;
+}
+
 bool TriCoreLegalizerInfo::legalizeFCmp(MachineInstr &MI,
                                         MachineRegisterInfo &MRI,
                                         MachineIRBuilder &MIRBuilder) const {

llvm/lib/Target/TriCore/TriCoreLegalizerInfo.h

@@ -37,6 +37,8 @@ class TriCoreLegalizerInfo : public LegalizerInfo {
 private:
   bool legalizeFCmp(MachineInstr &MI, MachineRegisterInfo &MRI,
                     MachineIRBuilder &MIRBuilder) const;
+  bool legalizeIntrinsicTrunc(MachineInstr &MI, MachineRegisterInfo &MRI,
+                              MachineIRBuilder &MIRBuilder) const;
   bool legalizeVaArg(MachineInstr &MI, MachineRegisterInfo &MRI,
                     MachineIRBuilder &MIRBuilder) const;
   void setFCmpLibcalls();

llvm/test/CodeGen/TriCore/GlobalIsel/legalize-intrinsic-trunc.mir

@@ -0,0 +1,41 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
+# RUN: llc -O0 -mtriple=tricore -global-isel -run-pass=legalizer \
+# RUN:   -verify-machineinstrs %s -o - | FileCheck %s
+
+---
+name:            intrinsic_trunc_s32
+body:             |
+  bb.0:
+    liveins: $d4
+
+    ; CHECK-LABEL: name: intrinsic_trunc_s32
+    ; CHECK: [[COPY:%[0-9]+]]:_(s32) = COPY $d4
+    ; CHECK: ADJCALLSTACKDOWN 0, 0, implicit-def $a10, implicit $a10
+    ; CHECK: $d4 = COPY [[COPY]](s32)
+    ; CHECK: CALL &truncf, csr_tricore_uppercontext, implicit-def $a11, implicit $psw, implicit $d4, implicit-def $d2
+    ; CHECK: [[COPY1:%[0-9]+]]:_(s32) = COPY $d2
+    ; CHECK: ADJCALLSTACKUP 0, 0, implicit-def $a10, implicit $a10
+    ; CHECK: $d4 = COPY [[COPY1]](s32)
+    %0:_(s32) = COPY $d4
+    %1:_(s32) = G_INTRINSIC_TRUNC %0(s32)
+    $d4 = COPY %1(s32)
+...
+
+---
+name:            intrinsic_trunc_s64
+body:             |
+  bb.0:
+    liveins: $d4
+
+    ; CHECK-LABEL: name: intrinsic_trunc_s64
+    ; CHECK: [[COPY:%[0-9]+]]:_(s64) = COPY $e4
+    ; CHECK: ADJCALLSTACKDOWN 0, 0, implicit-def $a10, implicit $a10
+    ; CHECK: $e4 = COPY [[COPY]](s64)
+    ; CHECK: CALL &trunc, csr_tricore_uppercontext, implicit-def $a11, implicit $psw, implicit $e4, implicit-def $e2
+    ; CHECK: [[COPY1:%[0-9]+]]:_(s64) = COPY $e2
+    ; CHECK: ADJCALLSTACKUP 0, 0, implicit-def $a10, implicit $a10
+    ; CHECK: $e4 = COPY [[COPY1]](s64)
+    %0:_(s64) = COPY $e4
+    %1:_(s64) = G_INTRINSIC_TRUNC %0(s64)
+    $e4 = COPY %1(s64)
+...