[llvm] r352763 - [ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader
Teresa Johnson via llvm-commits
llvm-commits at lists.llvm.org
Thu Jan 31 08:00:16 PST 2019
Author: tejohnson
Date: Thu Jan 31 08:00:15 2019
New Revision: 352763
URL: http://llvm.org/viewvc/llvm-project?rev=352763&view=rev
Log:
[ThinLTO] Rename COMDATs for COFF when promoting/renaming COMDAT leader
Summary:
COFF requires that COMDAT name match that of the leader. When we promote
and rename an internal leader in ThinLTO due to an import, ensure we
subsequently rename the associated COMDAT. Similar to D31963 which did
this during ThinLTO module splitting.
Fixes PR40414.
Reviewers: pcc, inglorion
Subscribers: mehdi_amini, dexonsmith, dmajor, llvm-commits
Differential Revision: https://reviews.llvm.org/D57395
Added:
llvm/trunk/test/Transforms/FunctionImport/Inputs/comdat.ll
llvm/trunk/test/Transforms/FunctionImport/comdat.ll
Modified:
llvm/trunk/include/llvm/Transforms/Utils/FunctionImportUtils.h
llvm/trunk/lib/Transforms/Utils/FunctionImportUtils.cpp
Modified: llvm/trunk/include/llvm/Transforms/Utils/FunctionImportUtils.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/FunctionImportUtils.h?rev=352763&r1=352762&r2=352763&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/FunctionImportUtils.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/FunctionImportUtils.h Thu Jan 31 08:00:15 2019
@@ -43,6 +43,11 @@ class FunctionImportGlobalProcessing {
/// to promote any non-renamable values.
SmallPtrSet<GlobalValue *, 8> Used;
+ /// Keep track of any COMDATs that require renaming (because COMDAT
+ /// leader was promoted and renamed). Maps from original COMDAT to one
+ /// with new name.
+ DenseMap<const Comdat *, Comdat *> RenamedComdats;
+
/// Check if we should promote the given local value to global scope.
bool shouldPromoteLocalToGlobal(const GlobalValue *SGV);
Modified: llvm/trunk/lib/Transforms/Utils/FunctionImportUtils.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/FunctionImportUtils.cpp?rev=352763&r1=352762&r2=352763&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/FunctionImportUtils.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/FunctionImportUtils.cpp Thu Jan 31 08:00:15 2019
@@ -248,6 +248,7 @@ void FunctionImportGlobalProcessing::pro
bool DoPromote = false;
if (GV.hasLocalLinkage() &&
((DoPromote = shouldPromoteLocalToGlobal(&GV)) || isPerformingImport())) {
+ auto Name = GV.getName();
// Once we change the name or linkage it is difficult to determine
// again whether we should promote since shouldPromoteLocalToGlobal needs
// to locate the summary (based on GUID from name and linkage). Therefore,
@@ -256,6 +257,12 @@ void FunctionImportGlobalProcessing::pro
GV.setLinkage(getLinkage(&GV, DoPromote));
if (!GV.hasLocalLinkage())
GV.setVisibility(GlobalValue::HiddenVisibility);
+
+ // If we are renaming a COMDAT leader, ensure that we record the COMDAT
+ // for later renaming as well. This is required for COFF.
+ if (const auto *C = GV.getComdat())
+ if (C->getName() == Name)
+ RenamedComdats.try_emplace(C, M.getOrInsertComdat(GV.getName()));
} else
GV.setLinkage(getLinkage(&GV, /* DoPromote */ false));
@@ -280,6 +287,16 @@ void FunctionImportGlobalProcessing::pro
processGlobalForThinLTO(SF);
for (GlobalAlias &GA : M.aliases())
processGlobalForThinLTO(GA);
+
+ // Replace any COMDATS that required renaming (because the COMDAT leader was
+ // promoted and renamed).
+ if (!RenamedComdats.empty())
+ for (auto &GO : M.global_objects())
+ if (auto *C = GO.getComdat()) {
+ auto Replacement = RenamedComdats.find(C);
+ if (Replacement != RenamedComdats.end())
+ GO.setComdat(Replacement->second);
+ }
}
bool FunctionImportGlobalProcessing::run() {
Added: llvm/trunk/test/Transforms/FunctionImport/Inputs/comdat.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/FunctionImport/Inputs/comdat.ll?rev=352763&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/FunctionImport/Inputs/comdat.ll (added)
+++ llvm/trunk/test/Transforms/FunctionImport/Inputs/comdat.ll Thu Jan 31 08:00:15 2019
@@ -0,0 +1,10 @@
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc19.0.24215"
+
+define void @main() {
+entry:
+ call i8* @lwt_fun()
+ ret void
+}
+
+declare i8* @lwt_fun()
Added: llvm/trunk/test/Transforms/FunctionImport/comdat.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/FunctionImport/comdat.ll?rev=352763&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/FunctionImport/comdat.ll (added)
+++ llvm/trunk/test/Transforms/FunctionImport/comdat.ll Thu Jan 31 08:00:15 2019
@@ -0,0 +1,32 @@
+; Test to ensure that comdat is renamed consistently when comdat leader is
+; promoted and renamed due to an import. Required by COFF.
+
+; REQUIRES: x86-registered-target
+
+; RUN: opt -thinlto-bc -o %t1.bc %s
+; RUN: opt -thinlto-bc -o %t2.bc %S/Inputs/comdat.ll
+; RUN: llvm-lto2 run -save-temps -o %t3 %t1.bc %t2.bc \
+; RUN: -r %t1.bc,lwt_fun,plx \
+; RUN: -r %t2.bc,main,plx \
+; RUN: -r %t2.bc,lwt_fun,
+; RUN: llvm-dis -o - %t3.1.3.import.bc | FileCheck %s
+
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc19.0.24215"
+
+; CHECK: $lwt.llvm.[[HASH:[0-9]+]] = comdat any
+$lwt = comdat any
+
+; CHECK: @lwt_aliasee = private unnamed_addr global {{.*}}, comdat($lwt.llvm.[[HASH]])
+ at lwt_aliasee = private unnamed_addr global [1 x i8*] [i8* null], comdat($lwt)
+
+; CHECK: @lwt.llvm.[[HASH]] = hidden unnamed_addr alias
+ at lwt = internal unnamed_addr alias [1 x i8*], [1 x i8*]* @lwt_aliasee
+
+; Below function should get imported into other module, resulting in @lwt being
+; promoted and renamed.
+define i8* @lwt_fun() {
+ %1 = getelementptr inbounds [1 x i8*], [1 x i8*]* @lwt, i32 0, i32 0
+ %2 = load i8*, i8** %1
+ ret i8* %2
+}
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