[GlobalISel] IRTranslator: Add MachineMemOperand to target memory intrinsics

[qcolombet]

LGTM

llvm/trunk/lib/CodeGen/GlobalISel/IRTranslator.cpp

MachineInstrBuilder MIB =
       MIRBuilder.buildIntrinsic(ID, Res, !CI.doesNotAccessMemory());
 
   for (auto &Arg : CI.arg_operands()) {
     // Some intrinsics take metadata parameters. Reject them.
     if (isa<MetadataAsValue>(Arg))
       return false;
     MIB.addUse(getOrCreateVReg(*Arg));
   }
+
+  // Add a MachineMemOperand if it is a target mem intrinsic.
+  const TargetLowering &TLI = *MF->getSubtarget().getTargetLowering();
+  TargetLowering::IntrinsicInfo Info;
+  // TODO: Add a GlobalISel version of getTgtMemIntrinsic.
+  if (TLI.getTgtMemIntrinsic(Info, CI, ID)) {
+    MachineMemOperand::Flags Flags =
+        Info.vol ? MachineMemOperand::MOVolatile : MachineMemOperand::MONone;
+    Flags |=
+        Info.readMem ? MachineMemOperand::MOLoad : MachineMemOperand::MOStore;
+    uint64_t Size = Info.memVT.getSizeInBits() >> 3;
+    MIB.addMemOperand(MF->getMachineMemOperand(MachinePointerInfo(Info.ptrVal),
+                                               Flags, Size, Info.align));
+  }
+
   return true;
 }
 
 bool IRTranslator::translateInvoke(const User &U,
                                    MachineIRBuilder &MIRBuilder) {
   const InvokeInst &I = cast<InvokeInst>(U);
   MCContext &Context = MF->getContext();
 

llvm/trunk/test/CodeGen/AArch64/GlobalISel/arm64-irtranslator.ll

 ; CHECK-LABEL: test_constant_vector
 ; CHECK: [[UNDEF:%[0-9]+]](s16) = IMPLICIT_DEF
 ; CHECK: [[F:%[0-9]+]](s16) = G_FCONSTANT half 0xH3C00
 ; CHECK: [[M:%[0-9]+]](<4 x s16>) = G_MERGE_VALUES [[UNDEF]](s16), [[UNDEF]](s16), [[UNDEF]](s16), [[F]](s16)
 ; CHECK: %d0 = COPY [[M]](<4 x s16>)
 define <4 x half> @test_constant_vector() {
   ret <4 x half> <half undef, half undef, half undef, half 0xH3C00>
 }
+
+define i32 @test_target_mem_intrinsic(i32* %addr) {
+; CHECK-LABEL: name: test_target_mem_intrinsic
+; CHECK: [[ADDR:%[0-9]+]](p0) = COPY %x0
+; CHECK: [[VAL:%[0-9]+]](s64) = G_INTRINSIC_W_SIDE_EFFECTS intrinsic(@llvm.aarch64.ldxr), [[ADDR]](p0) :: (volatile load 4 from %ir.addr)
+; CHECK: G_TRUNC [[VAL]](s64)
+  %val = call i64 @llvm.aarch64.ldxr.p0i32(i32* %addr)
+  %trunc = trunc i64 %val to i32
+  ret i32 %trunc
+}
+
+declare i64 @llvm.aarch64.ldxr.p0i32(i32*) nounwind