From e74191633036905388245818f54553813c880f83 Mon Sep 17 00:00:00 2001 From: Sriraman Tallam Date: Wed, 17 Feb 2021 12:34:37 -0800 Subject: [PATCH] Basic block sections should enable not function sections implicitly. Basic block sections enables function sections implicitly, this is not needed and is inefficient with "=list" option. We had basic block sections enable function sections implicitly in clang. This is particularly inefficient with "=list" option as it places functions that do not have any basic block sections in separate sections. This causes unnecessary object file overhead for large applications. This patch disables this implicit behavior. It only creates function sections for those functions that require basic block sections. This patch is the second of two patches and this patch removes the implicit enabling of function sections with basic block sections in clang. Differential Revision: https://reviews.llvm.org/D93876 --- clang/lib/Frontend/CompilerInvocation.cpp | 7 ++----- clang/test/CodeGen/basic-block-sections.c | 5 ++--- 2 files changed, 4 insertions(+), 8 deletions(-) diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index f929647..a49c978 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -1383,8 +1383,7 @@ void CompilerInvocation::GenerateCodeGenArgs( GenerateArg(Args, OPT_ftime_report, SA); } - if (Opts.FunctionSections && - (Opts.BBSections == "none" || Opts.BBSections == "labels")) + if (Opts.FunctionSections) GenerateArg(Args, OPT_ffunction_sections, SA); if (Opts.PrepareForLTO && !Opts.PrepareForThinLTO) @@ -1678,9 +1677,7 @@ bool CompilerInvocation::ParseCodeGenArgsImpl(CodeGenOptions &Opts, } // Basic Block Sections implies Function Sections. - Opts.FunctionSections = - Args.hasArg(OPT_ffunction_sections) || - (Opts.BBSections != "none" && Opts.BBSections != "labels"); + Opts.FunctionSections = Args.hasArg(OPT_ffunction_sections); Opts.PrepareForLTO = Args.hasArg(OPT_flto, OPT_flto_EQ); Opts.PrepareForThinLTO = false; diff --git a/clang/test/CodeGen/basic-block-sections.c b/clang/test/CodeGen/basic-block-sections.c index ee0dc90..a61b8dd 100644 --- a/clang/test/CodeGen/basic-block-sections.c +++ b/clang/test/CodeGen/basic-block-sections.c @@ -32,10 +32,9 @@ int another(int a) { // BB_WORLD: world: // BB_WORLD: .section .text.world,"ax",@progbits,unique // BB_WORLD: world.__part.1: -// BB_WORLD: .section .text.another,"ax",@progbits -// BB_ALL: .section .text.another,"ax",@progbits,unique +// BB_ALL: .section .text.another,"ax",@progbits // BB_ALL: another.__part.1: -// BB_LIST-NOT: .section .text.another,"ax",@progbits,unique +// BB_LIST-NOT: .section .text.another,"ax",@progbits // BB_LIST: another: // BB_LIST-NOT: another.__part.1: // -- 2.7.4