1//===--- SingleWorkItemBarrierCheck.cpp - clang-tidy-----------------------===//
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#include "SingleWorkItemBarrierCheck.h"
10#include "clang/AST/ASTContext.h"
11#include "clang/ASTMatchers/ASTMatchFinder.h"
12
13using namespace clang::ast_matchers;
14
15namespace clang::tidy::altera {
16
17void SingleWorkItemBarrierCheck::registerMatchers(MatchFinder *Finder) {
18 // Find any function that calls barrier but does not call an ID function.
19 // hasAttr(attr::Kind::DeviceKernel) restricts it to only kernel functions.
20 // FIXME: Have it accept all functions but check for a parameter that gets an
21 // ID from one of the four ID functions.
22 Finder->addMatcher(
23 // Find function declarations...
24 functionDecl(
25 // That are device kernels...
26 hasAttr(attr::Kind::DeviceKernel),
27 // And call a barrier function (either 1.x or 2.x version)...
28 forEachDescendant(callExpr(callee(functionDecl(hasAnyName(
29 "barrier", "work_group_barrier"))))
30 .bind("barrier")),
31 // But do not call an ID function.
32 unless(hasDescendant(callExpr(callee(functionDecl(
33 hasAnyName("get_global_id", "get_local_id", "get_group_id",
34 "get_local_linear_id")))))))
35 .bind("function"),
36 this);
37}
38
39void SingleWorkItemBarrierCheck::check(const MatchFinder::MatchResult &Result) {
40 const auto *MatchedDecl = Result.Nodes.getNodeAs<FunctionDecl>(ID: "function");
41 const auto *MatchedBarrier = Result.Nodes.getNodeAs<CallExpr>(ID: "barrier");
42 if (AOCVersion < 1701) {
43 // get_group_id and get_local_linear_id were added at/after v17.01
44 diag(MatchedDecl->getLocation(),
45 "kernel function %0 does not call 'get_global_id' or 'get_local_id' "
46 "and will be treated as a single work-item")
47 << MatchedDecl;
48 diag(Loc: MatchedBarrier->getBeginLoc(),
49 Description: "barrier call is in a single work-item and may error out",
50 Level: DiagnosticIDs::Note);
51 } else {
52 // If reqd_work_group_size is anything other than (1,1,1), it will be
53 // interpreted as an NDRange in AOC version >= 17.1.
54 bool IsNDRange = false;
55 if (MatchedDecl->hasAttr<ReqdWorkGroupSizeAttr>()) {
56 const auto *Attribute = MatchedDecl->getAttr<ReqdWorkGroupSizeAttr>();
57 auto Eval = [&](Expr *E) {
58 return E->EvaluateKnownConstInt(MatchedDecl->getASTContext())
59 .getExtValue();
60 };
61 if (Eval(Attribute->getXDim()) > 1 || Eval(Attribute->getYDim()) > 1 ||
62 Eval(Attribute->getZDim()) > 1)
63 IsNDRange = true;
64 }
65 if (IsNDRange) // No warning if kernel is treated as an NDRange.
66 return;
67 diag(MatchedDecl->getLocation(),
68 "kernel function %0 does not call an ID function and may be a viable "
69 "single work-item, but will be forced to execute as an NDRange")
70 << MatchedDecl;
71 diag(Loc: MatchedBarrier->getBeginLoc(),
72 Description: "barrier call will force NDRange execution; if single work-item "
73 "semantics are desired a mem_fence may be more efficient",
74 Level: DiagnosticIDs::Note);
75 }
76}
77
78void SingleWorkItemBarrierCheck::storeOptions(
79 ClangTidyOptions::OptionMap &Opts) {
80 Options.store(Options&: Opts, LocalName: "AOCVersion", Value: AOCVersion);
81}
82
83} // namespace clang::tidy::altera
84

source code of clang-tools-extra/clang-tidy/altera/SingleWorkItemBarrierCheck.cpp