From 56ddb2a69c92a417a93e8ccf3f8fe1ce047c78e3 Mon Sep 17 00:00:00 2001
From: "Michael J. Spencer" <bigcheesegs@gmail.com>
Date: Sat, 19 Oct 2019 01:36:37 +0000
Subject: [PATCH] [Implicit Modules] Add -cc1 option
-fmodules-strict-context-hash which includes search paths and diagnostics.
Differential Revision: https://reviews.llvm.org/D68528
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@375322 91177308-0d34-0410-b5e6-96231b3b80d8
---
docs/Modules.rst | 10 ++++++++
include/clang/Driver/CC1Options.td | 3 +++
include/clang/Lex/HeaderSearchOptions.h | 20 ++++++++++++++-
lib/Frontend/CompilerInvocation.cpp | 20 +++++++++++++++
test/Modules/context-hash.c | 33 +++++++++++++++++++++++++
5 files changed, 85 insertions(+), 1 deletion(-)
create mode 100644 test/Modules/context-hash.c
diff --git a/docs/Modules.rst b/docs/Modules.rst
index 34ad55a487..a1dc242f2b 100644
--- a/docs/Modules.rst
+++ b/docs/Modules.rst
@@ -225,6 +225,16 @@ Command-line parameters
``-fprebuilt-module-path=<directory>``
Specify the path to the prebuilt modules. If specified, we will look for modules in this directory for a given top-level module name. We don't need a module map for loading prebuilt modules in this directory and the compiler will not try to rebuild these modules. This can be specified multiple times.
+-cc1 Options
+^^^^^^^^^^^^
+
+``-fmodules-strict-context-hash``
+ Enables hashing of all compiler options that could impact the semantics of a
+ module in an implicit build. This includes things such as header search paths
+ and diagnostics. Using this option may lead to an excessive number of modules
+ being built if the command line arguments are not homogeneous across your
+ build.
+
Module Semantics
================
diff --git a/include/clang/Driver/CC1Options.td b/include/clang/Driver/CC1Options.td
index e0974fbb5a..4518aca82e 100644
--- a/include/clang/Driver/CC1Options.td
+++ b/include/clang/Driver/CC1Options.td
@@ -815,6 +815,9 @@ def fdisable_module_hash : Flag<["-"], "fdisable-module-hash">,
HelpText<"Disable the module hash">;
def fmodules_hash_content : Flag<["-"], "fmodules-hash-content">,
HelpText<"Enable hashing the content of a module file">;
+def fmodules_strict_context_hash : Flag<["-"], "fmodules-strict-context-hash">,
+ HelpText<"Enable hashing of all compiler options that could impact the "
+ "semantics of a module in an implicit build">;
def c_isystem : JoinedOrSeparate<["-"], "c-isystem">, MetaVarName<"<directory>">,
HelpText<"Add directory to the C SYSTEM include search path">;
def objc_isystem : JoinedOrSeparate<["-"], "objc-isystem">,
diff --git a/include/clang/Lex/HeaderSearchOptions.h b/include/clang/Lex/HeaderSearchOptions.h
index 3c309744ba..5c19a41986 100644
--- a/include/clang/Lex/HeaderSearchOptions.h
+++ b/include/clang/Lex/HeaderSearchOptions.h
@@ -11,6 +11,7 @@
#include "clang/Basic/LLVM.h"
#include "llvm/ADT/CachedHashString.h"
+#include "llvm/ADT/Hashing.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/StringRef.h"
#include <cstdint>
@@ -206,6 +207,13 @@ public:
unsigned ModulesHashContent : 1;
+ /// Whether we should include all things that could impact the module in the
+ /// hash.
+ ///
+ /// This includes things like the full header search path, and enabled
+ /// diagnostics.
+ unsigned ModulesStrictContextHash : 1;
+
HeaderSearchOptions(StringRef _Sysroot = "/")
: Sysroot(_Sysroot), ModuleFormat("raw"), DisableModuleHash(false),
ImplicitModuleMaps(false), ModuleMapFileHomeIsCwd(false),
@@ -214,7 +222,8 @@ public:
ModulesValidateOncePerBuildSession(false),
ModulesValidateSystemHeaders(false),
ValidateASTInputFilesContent(false), UseDebugInfo(false),
- ModulesValidateDiagnosticOptions(true), ModulesHashContent(false) {}
+ ModulesValidateDiagnosticOptions(true), ModulesHashContent(false),
+ ModulesStrictContextHash(false) {}
/// AddPath - Add the \p Path path to the specified \p Group list.
void AddPath(StringRef Path, frontend::IncludeDirGroup Group,
@@ -238,6 +247,15 @@ public:
}
};
+inline llvm::hash_code hash_value(const HeaderSearchOptions::Entry &E) {
+ return llvm::hash_combine(E.Path, E.Group, E.IsFramework, E.IgnoreSysRoot);
+}
+
+inline llvm::hash_code
+hash_value(const HeaderSearchOptions::SystemHeaderPrefix &SHP) {
+ return llvm::hash_combine(SHP.Prefix, SHP.IsSystemHeader);
+}
+
} // namespace clang
#endif // LLVM_CLANG_LEX_HEADERSEARCHOPTIONS_H
diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 0aa44252c6..665695ec3b 100644
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -2067,6 +2067,7 @@ static void ParseHeaderSearchArgs(HeaderSearchOptions &Opts, ArgList &Args,
Opts.AddPrebuiltModulePath(A->getValue());
Opts.DisableModuleHash = Args.hasArg(OPT_fdisable_module_hash);
Opts.ModulesHashContent = Args.hasArg(OPT_fmodules_hash_content);
+ Opts.ModulesStrictContextHash = Args.hasArg(OPT_fmodules_strict_context_hash);
Opts.ModulesValidateDiagnosticOptions =
!Args.hasArg(OPT_fmodules_disable_diagnostic_validation);
Opts.ImplicitModuleMaps = Args.hasArg(OPT_fimplicit_module_maps);
@@ -3546,6 +3547,7 @@ std::string CompilerInvocation::getModuleHash() const {
using llvm::hash_code;
using llvm::hash_value;
using llvm::hash_combine;
+ using llvm::hash_combine_range;
// Start the signature with the compiler version.
// FIXME: We'd rather use something more cryptographically sound than
@@ -3600,6 +3602,24 @@ std::string CompilerInvocation::getModuleHash() const {
hsOpts.ModulesValidateDiagnosticOptions);
code = hash_combine(code, hsOpts.ResourceDir);
+ if (hsOpts.ModulesStrictContextHash) {
+ hash_code SHPC = hash_combine_range(hsOpts.SystemHeaderPrefixes.begin(),
+ hsOpts.SystemHeaderPrefixes.end());
+ hash_code UEC = hash_combine_range(hsOpts.UserEntries.begin(),
+ hsOpts.UserEntries.end());
+ code = hash_combine(code, hsOpts.SystemHeaderPrefixes.size(), SHPC,
+ hsOpts.UserEntries.size(), UEC);
+
+ const DiagnosticOptions &diagOpts = getDiagnosticOpts();
+ #define DIAGOPT(Name, Bits, Default) \
+ code = hash_combine(code, diagOpts.Name);
+ #define ENUM_DIAGOPT(Name, Type, Bits, Default) \
+ code = hash_combine(code, diagOpts.get##Name());
+ #include "clang/Basic/DiagnosticOptions.def"
+ #undef DIAGOPT
+ #undef ENUM_DIAGOPT
+ }
+
// Extend the signature with the user build path.
code = hash_combine(code, hsOpts.ModuleUserBuildPath);
diff --git a/test/Modules/context-hash.c b/test/Modules/context-hash.c
new file mode 100644
index 0000000000..c6eed706e2
--- /dev/null
+++ b/test/Modules/context-hash.c
@@ -0,0 +1,33 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fsyntax-only -internal-isystem \
+// RUN: %S/Inputs/System/usr/include -fmodules -fimplicit-module-maps \
+// RUN: -fmodules-cache-path=%t %s -Rmodule-build 2> %t1
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fsyntax-only -internal-isystem \
+// RUN: %S/Inputs/System/usr/include -internal-isystem %S -fmodules \
+// RUN: -fimplicit-module-maps -fmodules-cache-path=%t %s -Rmodule-build 2> \
+// RUN: %t2
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fsyntax-only -internal-isystem \
+// RUN: %S/Inputs/System/usr/include -internal-isystem %S -fmodules \
+// RUN: -fimplicit-module-maps -fmodules-cache-path=%t %s \
+// RUN: -fmodules-strict-context-hash -Rmodule-build 2> %t3
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -fsyntax-only -Weverything -internal-isystem \
+// RUN: %S/Inputs/System/usr/include -fmodules -fmodules-strict-context-hash \
+// RUN: -fimplicit-module-maps -fmodules-cache-path=%t %s -Rmodule-build 2> \
+// RUN: %t4
+// RUN: echo %t | cat - %t1 %t2 %t3 %t4 | FileCheck %s
+
+// This test verifies that only strict hashing includes search paths and
+// diagnostics in the module context hash.
+
+#include <stdio.h>
+
+// CHECK: [[PREFIX:(.*[/\\])+[a-zA-Z0-9.-]+]]
+// CHECK: building module 'cstd' as '[[PREFIX]]{{[/\\]}}[[CONTEXT_HASH:[A-Z0-9]+]]{{[/\\]}}cstd-[[AST_HASH:[A-Z0-9]+]].pcm'
+// CHECK: building module 'cstd' as '{{.*[/\\]}}[[CONTEXT_HASH]]{{[/\\]}}cstd-[[AST_HASH]].pcm'
+// CHECK-NOT: building module 'cstd' as '{{.*[/\\]}}[[CONTEXT_HASH]]{{[/\\]}}
+// CHECK: cstd-[[AST_HASH]].pcm'
+// CHECK-NOT: building module 'cstd' as '{{.*[/\\]}}[[CONTEXT_HASH]]{{[/\\]}}
+// CHECK: cstd-[[AST_HASH]].pcm'
--
2.40.0