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Differential D108647

[clang][deps] Use top-level modules as precompiled dependencies
ClosedPublic

Authored by jansvoboda11 on Aug 24 2021, 10:39 AM.

Details

Reviewers
Bigcheese
dexonsmith
arphaman
Commits
rG3b8f536fec2f: [clang][deps] Use top-level modules as precompiled dependencies
Summary

The ASTReader populates Module::PresumedModuleMapFile only for top-level modules, not submodules. To avoid generating empty -fmodule-map-file= arguments, make discovered modules depend on top-level precompiled modules. The granularity of submodules is not important here.

The documentation of Module::PresumedModuleMapFile says this field is non-empty only when building from preprocessed source. This means there can still be cases where the dependency scanner generates empty -fmodule-map-file= arguments. That's being addressed in separate patch: D108544.

Diff Detail

Event Timeline

jansvoboda11 requested review of this revision.Aug 24 2021, 10:39 AM
jansvoboda11 created this revision.
Herald added a project: Restricted Project. · View Herald TranscriptAug 24 2021, 10:39 AM
Herald added a subscriber: cfe-commits. · View Herald Transcript
jansvoboda11 mentioned this in D108544: [clang][deps] Avoid generating arguments for missing module map files.Aug 24 2021, 10:49 AM
Harbormaster completed remote builds in B120999: Diff 368394.Aug 24 2021, 11:24 AM
dexonsmith accepted this revision.Aug 24 2021, 3:44 PM

This LGTM.

The documentation of Module::PresumedModuleMapFile says this field is non-empty only when building from preprocessed source. This means there can still be cases where the dependency scanner generates empty -fmodule-map-file= arguments. That's being addressed in separate patch: D108544.

I think the documentation might be out of date since ab75597ddac52f24e9cbd794cded195262ef670e. I made a comment in D108544.

This revision is now accepted and ready to land.Aug 24 2021, 3:44 PM
Closed by commit rG3b8f536fec2f: [clang][deps] Use top-level modules as precompiled dependencies (authored by jansvoboda11). · Explain WhyAug 25 2021, 1:51 AM
This revision was automatically updated to reflect the committed changes.
jansvoboda11 added a commit: rG3b8f536fec2f: [clang][deps] Use top-level modules as precompiled dependencies.

Revision Contents

PathSize
clang/
lib/
Tooling/
DependencyScanning/
4 lines
test/
ClangScanDeps/
Inputs/
modules-pch-common-submodule/
7 lines
7 lines
1 line
11 lines
1 line
1 line
134 lines

Diff 368394

clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

Show First 20 Lines • Show All 240 Lines • ▼ Show 20 LinesModuleID ModuleDepCollectorPP::handleTopLevelModule(const Module *M) {
return MD.ID; return MD.ID;
} }
void ModuleDepCollectorPP::addDirectPrebuiltModuleDeps(const Module *M, void ModuleDepCollectorPP::addDirectPrebuiltModuleDeps(const Module *M,
ModuleDeps &MD) { ModuleDeps &MD) {
for (const Module *Import : M->Imports) for (const Module *Import : M->Imports)
if (Import->getTopLevelModule() != M->getTopLevelModule()) if (Import->getTopLevelModule() != M->getTopLevelModule())
if (MDC.isPrebuiltModule(Import)) if (MDC.isPrebuiltModule(Import->getTopLevelModule()))
MD.PrebuiltModuleDeps.emplace_back(Import); MD.PrebuiltModuleDeps.emplace_back(Import->getTopLevelModule());
} }
void ModuleDepCollectorPP::addAllSubmoduleDeps( void ModuleDepCollectorPP::addAllSubmoduleDeps(
const Module *M, ModuleDeps &MD, const Module *M, ModuleDeps &MD,
llvm::DenseSet<const Module *> &AddedModules) { llvm::DenseSet<const Module *> &AddedModules) {
addModuleDep(M, MD, AddedModules); addModuleDep(M, MD, AddedModules);
for (const Module *SubM : M->submodules()) for (const Module *SubM : M->submodules())
Show All 39 Lines

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/cdb_pch.json

  • This file was added.
[
{
"directory": "DIR",
"command": "clang -x c-header DIR/pch.h -fmodules -gmodules -fimplicit-module-maps -fmodules-cache-path=DIR/cache -o DIR/pch.h.gch",
"file": "DIR/pch.h"
}
]

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/cdb_tu.json

  • This file was added.
[
{
"directory": "DIR",
"command": "clang -fsyntax-only DIR/tu.c -fmodules -gmodules -fimplicit-module-maps -fmodules-cache-path=DIR/cache -include DIR/pch.h -o DIR/tu.o",
"file": "DIR/tu.c"
}
]

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/mod_common.h

  • This file was added.
This is an empty file.

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/mod_common_sub.h

  • This file was added.
This is an empty file.

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/mod_tu.h

  • This file was added.
#include "mod_common_sub.h"

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/module.modulemap

  • This file was added.
module ModCommon {
header "mod_common.h"
module ModCommonSub {
header "mod_common_sub.h"
}
}
module ModTU {
header "mod_tu.h"
}

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/pch.h

  • This file was added.
#include "mod_common.h"

clang/test/ClangScanDeps/Inputs/modules-pch-common-submodule/tu.c

  • This file was added.
#include "mod_tu.h"

clang/test/ClangScanDeps/modules-pch-common-submodule.c

  • This file was added.
// RUN: rm -rf %t && mkdir %t
// RUN: cp %S/Inputs/modules-pch-common-submodule/* %t
// Scan dependencies of the PCH:
//
// RUN: sed "s|DIR|%/t|g" %S/Inputs/modules-pch-common-submodule/cdb_pch.json > %t/cdb.json
// RUN: echo -%t > %t/result_pch.json
// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full \
// RUN: -generate-modules-path-args -module-files-dir %t/build >> %t/result_pch.json
// RUN: cat %t/result_pch.json | sed 's:\\\\\?:/:g' | FileCheck %s -check-prefix=CHECK-PCH
//
// CHECK-PCH: -[[PREFIX:.*]]
// CHECK-PCH-NEXT: {
// CHECK-PCH-NEXT: "modules": [
// CHECK-PCH-NEXT: {
// CHECK-PCH-NEXT: "clang-module-deps": [],
// CHECK-PCH-NEXT: "clang-modulemap-file": "[[PREFIX]]/module.modulemap",
// CHECK-PCH-NEXT: "command-line": [
// CHECK-PCH-NEXT: "-cc1"
// CHECK-PCH: "-emit-module"
// CHECK-PCH: "-fmodules"
// CHECK-PCH: "-fmodule-name=ModCommon"
// CHECK-PCH: "-fno-implicit-modules"
// CHECK-PCH: ],
// CHECK-PCH-NEXT: "context-hash": "[[HASH_MOD_COMMON:.*]]",
// CHECK-PCH-NEXT: "file-deps": [
// CHECK-PCH-NEXT: "[[PREFIX]]/mod_common.h",
// CHECK-PCH-NEXT: "[[PREFIX]]/mod_common_sub.h",
// CHECK-PCH-NEXT: "[[PREFIX]]/module.modulemap"
// CHECK-PCH-NEXT: ],
// CHECK-PCH-NEXT: "name": "ModCommon"
// CHECK-PCH-NEXT: }
// CHECK-PCH-NEXT: ],
// CHECK-PCH-NEXT: "translation-units": [
// CHECK-PCH-NEXT: {
// CHECK-PCH-NEXT: "clang-context-hash": "[[HASH_PCH:.*]]",
// CHECK-PCH-NEXT: "clang-module-deps": [
// CHECK-PCH-NEXT: {
// CHECK-PCH-NEXT: "context-hash": "[[HASH_MOD_COMMON]]",
// CHECK-PCH-NEXT: "module-name": "ModCommon"
// CHECK-PCH-NEXT: }
// CHECK-PCH-NEXT: ],
// CHECK-PCH-NEXT: "command-line": [
// CHECK-PCH-NEXT: "-fno-implicit-modules"
// CHECK-PCH-NEXT: "-fno-implicit-module-maps"
// CHECK-PCH-NEXT: "-fmodule-file=[[PREFIX]]/build/[[HASH_MOD_COMMON]]/ModCommon-{{.*}}.pcm"
// CHECK-PCH-NEXT: "-fmodule-map-file=[[PREFIX]]/module.modulemap"
// CHECK-PCH-NEXT: ],
// CHECK-PCH-NEXT: "file-deps": [
// CHECK-PCH-NEXT: "[[PREFIX]]/pch.h"
// CHECK-PCH-NEXT: ],
// CHECK-PCH-NEXT: "input-file": "[[PREFIX]]/pch.h"
// CHECK-PCH-NEXT: }
// CHECK-PCH-NEXT: ]
// CHECK-PCH-NEXT: }
// Explicitly build the PCH:
//
// RUN: tail -n +2 %t/result_pch.json > %t/result_pch_stripped.json
// RUN: %python %S/../../utils/module-deps-to-rsp.py %t/result_pch_stripped.json \
// RUN: --module-name=ModCommon > %t/mod_common.cc1.rsp
// RUN: %python %S/../../utils/module-deps-to-rsp.py %t/result_pch_stripped.json \
// RUN: --tu-index=0 > %t/pch.rsp
//
// RUN: %clang @%t/mod_common.cc1.rsp
// RUN: %clang -x c-header %t/pch.h -fmodules -gmodules -fimplicit-module-maps \
// RUN: -fmodules-cache-path=%t/cache -o %t/pch.h.gch @%t/pch.rsp
// Scan dependencies of the TU:
//
// RUN: sed "s|DIR|%/t|g" %S/Inputs/modules-pch-common-submodule/cdb_tu.json > %t/cdb.json
// RUN: echo -%t > %t/result_tu.json
// RUN: clang-scan-deps -compilation-database %t/cdb.json -format experimental-full \
// RUN: -generate-modules-path-args -module-files-dir %t/build >> %t/result_tu.json
// RUN: cat %t/result_tu.json | sed 's:\\\\\?:/:g' | FileCheck %s -check-prefix=CHECK-TU
//
// CHECK-TU: -[[PREFIX:.*]]
// CHECK-TU-NEXT: {
// CHECK-TU-NEXT: "modules": [
// CHECK-TU-NEXT: {
// CHECK-TU-NEXT: "clang-module-deps": [],
// CHECK-TU-NEXT: "clang-modulemap-file": "[[PREFIX]]/module.modulemap",
// CHECK-TU-NEXT: "command-line": [
// CHECK-TU-NEXT: "-cc1"
// CHECK-TU: "-fmodule-map-file=[[PREFIX]]/module.modulemap"
// CHECK-TU: "-emit-module"
// CHECK-TU: "-fmodule-file=[[PREFIX]]/build/[[HASH_MOD_COMMON:.*]]/ModCommon-{{.*}}.pcm"
// CHECK-TU: "-fmodules"
// CHECK-TU: "-fmodule-name=ModTU"
// CHECK-TU: "-fno-implicit-modules"
// CHECK-TU: ],
// CHECK-TU-NEXT: "context-hash": "[[HASH_MOD_TU:.*]]",
// CHECK-TU-NEXT: "file-deps": [
// CHECK-TU-NEXT: "[[PREFIX]]/mod_tu.h",
// CHECK-TU-NEXT: "[[PREFIX]]/module.modulemap"
// CHECK-TU-NEXT: ],
// CHECK-TU-NEXT: "name": "ModTU"
// CHECK-TU-NEXT: }
// CHECK-TU-NEXT: ],
// CHECK-TU-NEXT: "translation-units": [
// CHECK-TU-NEXT: {
// CHECK-TU-NEXT: "clang-context-hash": "[[HASH_TU:.*]]",
// CHECK-TU-NEXT: "clang-module-deps": [
// CHECK-TU-NEXT: {
// CHECK-TU-NEXT: "context-hash": "[[HASH_MOD_TU]]"
// CHECK-TU-NEXT: "module-name": "ModTU"
// CHECK-TU-NEXT: }
// CHECK-TU-NEXT: ],
// CHECK-TU-NEXT: "command-line": [
// CHECK-TU-NEXT: "-fno-implicit-modules",
// CHECK-TU-NEXT: "-fno-implicit-module-maps",
// CHECK-TU-NEXT: "-fmodule-file=[[PREFIX]]/build/[[HASH_MOD_TU:.*]]/ModTU-{{.*}}.pcm",
// CHECK-TU-NEXT: "-fmodule-map-file=[[PREFIX]]/module.modulemap"
// CHECK-TU-NEXT: ],
// CHECK-TU-NEXT: "file-deps": [
// CHECK-TU-NEXT: "[[PREFIX]]/tu.c",
// CHECK-TU-NEXT: "[[PREFIX]]/pch.h.gch"
// CHECK-TU-NEXT: ],
// CHECK-TU-NEXT: "input-file": "[[PREFIX]]/tu.c"
// CHECK-TU-NEXT: }
// CHECK-TU-NEXT: ]
// CHECK-TU-NEXT: }
// Explicitly build the TU:
//
// RUN: tail -n +2 %t/result_tu.json > %t/result_tu_stripped.json
// RUN: %python %S/../../utils/module-deps-to-rsp.py %t/result_tu_stripped.json \
// RUN: --module-name=ModTU > %t/mod_tu.cc1.rsp
// RUN: %python %S/../../utils/module-deps-to-rsp.py %t/result_tu_stripped.json \
// RUN: --tu-index=0 > %t/tu.rsp
//
// RUN: %clang @%t/mod_tu.cc1.rsp
// RUN: %clang -fsyntax-only %t/tu.c -fmodules -gmodules -fimplicit-module-maps \
// RUN: -fmodules-cache-path=%t/cache -include %t/pch.h -o %t/tu.o @%t/tu.rsp