1 | //===-- WebAssemblySubtarget.cpp - WebAssembly Subtarget Information ------===// |
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 WebAssembly-specific subclass of |
11 | /// TargetSubtarget. |
12 | /// |
13 | //===----------------------------------------------------------------------===// |
14 | |
15 | #include "WebAssemblySubtarget.h" |
16 | #include "MCTargetDesc/WebAssemblyMCTargetDesc.h" |
17 | #include "WebAssemblyInstrInfo.h" |
18 | #include "llvm/MC/TargetRegistry.h" |
19 | using namespace llvm; |
20 | |
21 | #define DEBUG_TYPE "wasm-subtarget" |
22 | |
23 | #define GET_SUBTARGETINFO_CTOR |
24 | #define GET_SUBTARGETINFO_TARGET_DESC |
25 | #include "WebAssemblyGenSubtargetInfo.inc" |
26 | |
27 | WebAssemblySubtarget & |
28 | WebAssemblySubtarget::initializeSubtargetDependencies(StringRef CPU, |
29 | StringRef FS) { |
30 | // Determine default and user-specified characteristics |
31 | LLVM_DEBUG(llvm::dbgs() << "initializeSubtargetDependencies\n" ); |
32 | |
33 | if (CPU.empty()) |
34 | CPU = "generic" ; |
35 | |
36 | ParseSubtargetFeatures(CPU, /*TuneCPU*/ CPU, FS); |
37 | |
38 | FeatureBitset Bits = getFeatureBits(); |
39 | |
40 | // bulk-memory implies bulk-memory-opt |
41 | if (HasBulkMemory) { |
42 | HasBulkMemoryOpt = true; |
43 | Bits.set(WebAssembly::FeatureBulkMemoryOpt); |
44 | } |
45 | |
46 | // reference-types implies call-indirect-overlong |
47 | if (HasReferenceTypes) { |
48 | HasCallIndirectOverlong = true; |
49 | Bits.set(WebAssembly::FeatureCallIndirectOverlong); |
50 | } |
51 | |
52 | // In case we changed any bits, update `MCSubtargetInfo`'s `FeatureBitset`. |
53 | setFeatureBits(Bits); |
54 | |
55 | return *this; |
56 | } |
57 | |
58 | WebAssemblySubtarget::WebAssemblySubtarget(const Triple &TT, |
59 | const std::string &CPU, |
60 | const std::string &FS, |
61 | const TargetMachine &TM) |
62 | : WebAssemblyGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS), |
63 | TargetTriple(TT), InstrInfo(initializeSubtargetDependencies(CPU, FS)), |
64 | TLInfo(TM, *this) {} |
65 | |
66 | bool WebAssemblySubtarget::enableAtomicExpand() const { |
67 | // If atomics are disabled, atomic ops are lowered instead of expanded |
68 | return hasAtomics(); |
69 | } |
70 | |
71 | bool WebAssemblySubtarget::enableMachineScheduler() const { |
72 | // Disable the MachineScheduler for now. Even with ShouldTrackPressure set and |
73 | // enableMachineSchedDefaultSched overridden, it appears to have an overall |
74 | // negative effect for the kinds of register optimizations we're doing. |
75 | return false; |
76 | } |
77 | |
78 | bool WebAssemblySubtarget::useAA() const { return true; } |
79 | |