1 //===-- WebAssemblySelectionDAGInfo.cpp - WebAssembly SelectionDAG Info ---===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// This file implements the WebAssemblySelectionDAGInfo class.
11 ///
12 //===----------------------------------------------------------------------===//
13
14 #include "WebAssemblyTargetMachine.h"
15 using namespace llvm;
16
17 #define DEBUG_TYPE "wasm-selectiondag-info"
18
19 WebAssemblySelectionDAGInfo::~WebAssemblySelectionDAGInfo() = default; // anchor
20
isTargetMemoryOpcode(unsigned Opcode) const21 bool WebAssemblySelectionDAGInfo::isTargetMemoryOpcode(unsigned Opcode) const {
22 switch (static_cast<WebAssemblyISD::NodeType>(Opcode)) {
23 default:
24 return false;
25 case WebAssemblyISD::GLOBAL_GET:
26 case WebAssemblyISD::GLOBAL_SET:
27 case WebAssemblyISD::TABLE_GET:
28 case WebAssemblyISD::TABLE_SET:
29 return true;
30 }
31 }
32
EmitTargetCodeForMemcpy(SelectionDAG & DAG,const SDLoc & DL,SDValue Chain,SDValue Dst,SDValue Src,SDValue Size,Align Alignment,bool IsVolatile,bool AlwaysInline,MachinePointerInfo DstPtrInfo,MachinePointerInfo SrcPtrInfo) const33 SDValue WebAssemblySelectionDAGInfo::EmitTargetCodeForMemcpy(
34 SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, SDValue Dst, SDValue Src,
35 SDValue Size, Align Alignment, bool IsVolatile, bool AlwaysInline,
36 MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
37 auto &ST = DAG.getMachineFunction().getSubtarget<WebAssemblySubtarget>();
38 if (!ST.hasBulkMemoryOpt())
39 return SDValue();
40
41 SDValue MemIdx = DAG.getConstant(0, DL, MVT::i32);
42 auto LenMVT = ST.hasAddr64() ? MVT::i64 : MVT::i32;
43
44 // Use `MEMCPY` here instead of `MEMORY_COPY` because `memory.copy` traps
45 // if the pointers are invalid even if the length is zero. `MEMCPY` gets
46 // extra code to handle this in the way that LLVM IR expects.
47 return DAG.getNode(
48 WebAssemblyISD::MEMCPY, DL, MVT::Other,
49 {Chain, MemIdx, MemIdx, Dst, Src, DAG.getZExtOrTrunc(Size, DL, LenMVT)});
50 }
51
EmitTargetCodeForMemmove(SelectionDAG & DAG,const SDLoc & DL,SDValue Chain,SDValue Op1,SDValue Op2,SDValue Op3,Align Alignment,bool IsVolatile,MachinePointerInfo DstPtrInfo,MachinePointerInfo SrcPtrInfo) const52 SDValue WebAssemblySelectionDAGInfo::EmitTargetCodeForMemmove(
53 SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, SDValue Op1, SDValue Op2,
54 SDValue Op3, Align Alignment, bool IsVolatile,
55 MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
56 return EmitTargetCodeForMemcpy(DAG, DL, Chain, Op1, Op2, Op3,
57 Alignment, IsVolatile, false,
58 DstPtrInfo, SrcPtrInfo);
59 }
60
EmitTargetCodeForMemset(SelectionDAG & DAG,const SDLoc & DL,SDValue Chain,SDValue Dst,SDValue Val,SDValue Size,Align Alignment,bool IsVolatile,bool AlwaysInline,MachinePointerInfo DstPtrInfo) const61 SDValue WebAssemblySelectionDAGInfo::EmitTargetCodeForMemset(
62 SelectionDAG &DAG, const SDLoc &DL, SDValue Chain, SDValue Dst, SDValue Val,
63 SDValue Size, Align Alignment, bool IsVolatile, bool AlwaysInline,
64 MachinePointerInfo DstPtrInfo) const {
65 auto &ST = DAG.getMachineFunction().getSubtarget<WebAssemblySubtarget>();
66 if (!ST.hasBulkMemoryOpt())
67 return SDValue();
68
69 SDValue MemIdx = DAG.getConstant(0, DL, MVT::i32);
70 auto LenMVT = ST.hasAddr64() ? MVT::i64 : MVT::i32;
71
72 // Use `MEMSET` here instead of `MEMORY_FILL` because `memory.fill` traps
73 // if the pointers are invalid even if the length is zero. `MEMSET` gets
74 // extra code to handle this in the way that LLVM IR expects.
75 //
76 // Only low byte matters for val argument, so anyext the i8
77 return DAG.getNode(WebAssemblyISD::MEMSET, DL, MVT::Other, Chain, MemIdx, Dst,
78 DAG.getAnyExtOrTrunc(Val, DL, MVT::i32),
79 DAG.getZExtOrTrunc(Size, DL, LenMVT));
80 }
81