From 37b80122bd1225eb8889d42b4fd5d7d383a329e7 Mon Sep 17 00:00:00 2001 From: Teresa Johnson Date: Fri, 10 May 2019 20:08:24 +0000 Subject: [ThinLTO] Auto-hide prevailing linkonce_odr only when all copies eligible Summary: We hit undefined references building with ThinLTO when one source file contained explicit instantiations of a template method (weak_odr) but there were also implicit instantiations in another file (linkonce_odr), and the latter was the prevailing copy. In this case the symbol was marked hidden when the prevailing linkonce_odr copy was promoted to weak_odr. It led to unsats when the resulting shared library was linked with other code that contained a reference (expecting to be resolved due to the explicit instantiation). Add a CanAutoHide flag to the GV summary to allow the thin link to identify when all copies are eligible for auto-hiding (because they were all originally linkonce_odr global unnamed addr), and only do the auto-hide in that case. Most of the changes here are due to plumbing the new flag through the bitcode and llvm assembly, and resulting test changes. I augmented the existing auto-hide test to check for this situation. Reviewers: pcc Subscribers: mehdi_amini, inglorion, eraman, dexonsmith, arphaman, dang, llvm-commits, steven_wu, wmi Tags: #llvm Differential Revision: https://reviews.llvm.org/D59709 llvm-svn: 360466 --- llvm/test/Bitcode/thinlto-function-summary-refgraph.ll | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'llvm/test/Bitcode/thinlto-function-summary-refgraph.ll') diff --git a/llvm/test/Bitcode/thinlto-function-summary-refgraph.ll b/llvm/test/Bitcode/thinlto-function-summary-refgraph.ll index e8a2a77..8211df9 100644 --- a/llvm/test/Bitcode/thinlto-function-summary-refgraph.ll +++ b/llvm/test/Bitcode/thinlto-function-summary-refgraph.ll @@ -148,17 +148,17 @@ entry: ; order, which depends on GUID, and the private function Y GUID will depend ; on the path to the test. ; DIS: ^0 = module: (path: "{{.*}}", hash: (0, 0, 0, 0, 0)) -; DIS-DAG: = gv: (name: "Z", summaries: (function: (module: ^0, flags: (linkage: linkonce_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 2, calls: ((callee: ^{{.*}}))))) ; guid = 104084381700047393 -; DIS-DAG: = gv: (name: "X", summaries: (function: (module: ^0, flags: (linkage: available_externally, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 2, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 1881667236089500162 -; DIS-DAG: = gv: (name: "W", summaries: (function: (module: ^0, flags: (linkage: weak_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 2, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 5790125716599269729 +; DIS-DAG: = gv: (name: "Z", summaries: (function: (module: ^0, flags: (linkage: linkonce_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 2, calls: ((callee: ^{{.*}}))))) ; guid = 104084381700047393 +; DIS-DAG: = gv: (name: "X", summaries: (function: (module: ^0, flags: (linkage: available_externally, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 2, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 1881667236089500162 +; DIS-DAG: = gv: (name: "W", summaries: (function: (module: ^0, flags: (linkage: weak_odr, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 2, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 5790125716599269729 ; DIS-DAG: = gv: (name: "foo") ; guid = 6699318081062747564 ; DIS-DAG: = gv: (name: "func") ; guid = 7289175272376759421 ; DIS-DAG: = gv: (name: "func3") ; guid = 11517462787082255043 -; DIS-DAG: = gv: (name: "globalvar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), varFlags: (readonly: 1)))) ; guid = 12887606300320728018 +; DIS-DAG: = gv: (name: "globalvar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1)))) ; guid = 12887606300320728018 ; DIS-DAG: = gv: (name: "func2") ; guid = 14069196320850861797 ; DIS-DAG: = gv: (name: "llvm.ctpop.i8") ; guid = 15254915475081819833 -; DIS-DAG: = gv: (name: "main", summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), insts: 9, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 15822663052811949562 -; DIS-DAG: = gv: (name: "bar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0), varFlags: (readonly: 1), refs: (^{{.*}})))) ; guid = 16434608426314478903 +; DIS-DAG: = gv: (name: "main", summaries: (function: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), insts: 9, calls: ((callee: ^{{.*}})), refs: (^{{.*}})))) ; guid = 15822663052811949562 +; DIS-DAG: = gv: (name: "bar", summaries: (variable: (module: ^0, flags: (linkage: external, notEligibleToImport: 0, live: 0, dsoLocal: 0, canAutoHide: 0), varFlags: (readonly: 1), refs: (^{{.*}})))) ; guid = 16434608426314478903 ; Don't try to match the exact GUID. Since it is private, the file path ; will get hashed, and that will be test dependent. -; DIS-DAG: = gv: (name: "Y", summaries: (function: (module: ^0, flags: (linkage: private, notEligibleToImport: 0, live: 0, dsoLocal: 1), insts: 14, calls: ((callee: ^{{.*}}))))) ; guid = +; DIS-DAG: = gv: (name: "Y", summaries: (function: (module: ^0, flags: (linkage: private, notEligibleToImport: 0, live: 0, dsoLocal: 1, canAutoHide: 0), insts: 14, calls: ((callee: ^{{.*}}))))) ; guid = -- cgit v1.1