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| author | John Brawn <john.brawn@arm.com> | 2017-06-02 10:24:14 +0000 |
|---|---|---|
| committer | John Brawn <john.brawn@arm.com> | 2017-06-02 10:24:14 +0000 |
| commit | 6671616cdeeb98b15c411d77d9d8c0466fab1bdb (patch) | |
| tree | 994ebb1467c1060ec0c6a6cebbef09ba6e304613 | |
| parent | e7aa90987d2e4fe71ab683ebca80a01d29d4ff7b (diff) | |
| download | bcm5719-llvm-6671616cdeeb98b15c411d77d9d8c0466fab1bdb.tar.gz bcm5719-llvm-6671616cdeeb98b15c411d77d9d8c0466fab1bdb.zip | |
[GlobalMerge] Don't merge globals that may be preempted
When a global may be preempted it needs to be accessed directly, instead of
indirectly through a MergedGlobals symbol, for the preemption to work.
This fixes PR33136.
Differential Revision: https://reviews.llvm.org/D33727
llvm-svn: 304537
| -rw-r--r-- | llvm/lib/CodeGen/GlobalMerge.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/CodeGen/ARM/global-merge-external.ll | 1 |
2 files changed, 5 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/GlobalMerge.cpp b/llvm/lib/CodeGen/GlobalMerge.cpp index 23812a2a234..3603f9b7ed9 100644 --- a/llvm/lib/CodeGen/GlobalMerge.cpp +++ b/llvm/lib/CodeGen/GlobalMerge.cpp @@ -556,6 +556,10 @@ bool GlobalMerge::doInitialization(Module &M) { if (GV.isDeclaration() || GV.isThreadLocal() || GV.hasSection()) continue; + // It's not safe to merge globals that may be preempted + if (TM && !TM->shouldAssumeDSOLocal(M, &GV)) + continue; + if (!(MergeExternalGlobals && GV.hasExternalLinkage()) && !GV.hasInternalLinkage()) continue; diff --git a/llvm/test/CodeGen/ARM/global-merge-external.ll b/llvm/test/CodeGen/ARM/global-merge-external.ll index a9e0d199705..03c97761432 100644 --- a/llvm/test/CodeGen/ARM/global-merge-external.ll +++ b/llvm/test/CodeGen/ARM/global-merge-external.ll @@ -2,6 +2,7 @@ ; RUN: llc < %s -mtriple=arm-eabi -arm-global-merge -global-merge-on-external=true | FileCheck %s --check-prefix=CHECK-MERGE ; RUN: llc < %s -mtriple=arm-eabi -arm-global-merge -global-merge-on-external=false | FileCheck %s --check-prefix=CHECK-NO-MERGE ; RUN: llc < %s -mtriple=arm-macho -arm-global-merge | FileCheck %s --check-prefix=CHECK-NO-MERGE +; RUN: llc < %s -mtriple=arm-eabi -arm-global-merge -relocation-model=pic | FileCheck %s --check-prefix=CHECK-NO-MERGE @x = global i32 0, align 4 @y = global i32 0, align 4 |
