1 //=- WebAssemblyMachineFunctionInfo.cpp - WebAssembly Machine Function Info -=//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// This file implements WebAssembly-specific per-machine-function
12 /// information.
13 ///
14 //===----------------------------------------------------------------------===//
15
16 #include "WebAssemblyMachineFunctionInfo.h"
17 #include "WebAssemblyISelLowering.h"
18 #include "WebAssemblySubtarget.h"
19 #include "llvm/CodeGen/Analysis.h"
20 using namespace llvm;
21
~WebAssemblyFunctionInfo()22 WebAssemblyFunctionInfo::~WebAssemblyFunctionInfo() {}
23
initWARegs()24 void WebAssemblyFunctionInfo::initWARegs() {
25 assert(WARegs.empty());
26 unsigned Reg = UnusedReg;
27 WARegs.resize(MF.getRegInfo().getNumVirtRegs(), Reg);
28 }
29
ComputeLegalValueVTs(const Function & F,const TargetMachine & TM,Type * Ty,SmallVectorImpl<MVT> & ValueVTs)30 void llvm::ComputeLegalValueVTs(const Function &F, const TargetMachine &TM,
31 Type *Ty, SmallVectorImpl<MVT> &ValueVTs) {
32 const DataLayout &DL(F.getParent()->getDataLayout());
33 const WebAssemblyTargetLowering &TLI =
34 *TM.getSubtarget<WebAssemblySubtarget>(F).getTargetLowering();
35 SmallVector<EVT, 4> VTs;
36 ComputeValueVTs(TLI, DL, Ty, VTs);
37
38 for (EVT VT : VTs) {
39 unsigned NumRegs = TLI.getNumRegisters(F.getContext(), VT);
40 MVT RegisterVT = TLI.getRegisterType(F.getContext(), VT);
41 for (unsigned i = 0; i != NumRegs; ++i)
42 ValueVTs.push_back(RegisterVT);
43 }
44 }
45
ComputeSignatureVTs(const Function & F,const TargetMachine & TM,SmallVectorImpl<MVT> & Params,SmallVectorImpl<MVT> & Results)46 void llvm::ComputeSignatureVTs(const Function &F, const TargetMachine &TM,
47 SmallVectorImpl<MVT> &Params,
48 SmallVectorImpl<MVT> &Results) {
49 ComputeLegalValueVTs(F, TM, F.getReturnType(), Results);
50
51 if (Results.size() > 1) {
52 // WebAssembly currently can't lower returns of multiple values without
53 // demoting to sret (see WebAssemblyTargetLowering::CanLowerReturn). So
54 // replace multiple return values with a pointer parameter.
55 Results.clear();
56 Params.push_back(
57 MVT::getIntegerVT(TM.createDataLayout().getPointerSizeInBits()));
58 }
59
60 for (auto &Arg : F.args())
61 ComputeLegalValueVTs(F, TM, Arg.getType(), Params);
62 }
63