[AddressSanitizer] Only instrument globals of default address space

[Ka-Ka]

Summary

The address sanitizer ignore memory accesses from different address spaces, however
when instrumenting globals the check for different address spaces is missing. This
result in assertion failure. The fault was found in an out of tree target.

The patch skip all globals of non default address space.

[vitalybuka]

the rest is LGTM

test/Instrumentation/AddressSanitizer/global_addrspace.ll

39

can you please remove unnecessary stuff, e.g. debug info

lib/Transforms/Instrumentation/AddressSanitizer.cpp

bool ModuleAddressSanitizer::ShouldInstrumentGlobal(GlobalVariable *G) {
   Type *Ty = G->getValueType();
   LLVM_DEBUG(dbgs() << "GLOBAL: " << *G << "\n");
 
   // FIXME: Metadata should be attched directly to the global directly instead
   // of being added to llvm.asan.globals.
   if (GlobalsMD.get(G).IsBlacklisted) return false;
   if (!Ty->isSized()) return false;
   if (!G->hasInitializer()) return false;
+  // Only instrument globals of default address spaces
+  if (G->getAddressSpace()) return false;
   if (GlobalWasGeneratedByCompiler(G)) return false; // Our own globals.
   // Two problems with thread-locals:
   //   - The address of the main thread's copy can't be computed at link-time.
   //   - Need to poison all copies, not just the main thread's one.
   if (G->isThreadLocal()) return false;
   // For now, just ignore this Global if the alignment is large.
   if (G->getAlignment() > MinRedzoneSizeForGlobal()) return false;
 

test/Instrumentation/AddressSanitizer/global_addrspace.ll

+; Only verify that asan don't crash on global variables of different
+; address space. The global variable should be unmodified by asan.
+
+; RUN: opt < %s -asan -asan-module -S | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@a = internal addrspace(42) global [1 x i32] zeroinitializer, align 4
+
+; CHECK: @a = internal addrspace(42) global [1 x i32] zeroinitializer, align 4
+
+define void @b(i32 %c) {
+entry:
+  %conv = sext i32 %c to i64
+  %0 = inttoptr i64 %conv to i32 addrspace(42)*
+  %cmp = icmp ugt i32 addrspace(42)* %0, getelementptr inbounds ([1 x i32], [1 x i32] addrspace(42)* @a, i64 0, i64 0)
+  br i1 %cmp, label %if.then, label %if.end
+
+if.then:
+  %call = tail call i32 (...) @e()
+  br label %if.end
+
+if.end:
+  ret void
+}
+
+declare i32 @e(...)
+
+!llvm.dbg.cu = !{!0}
+!llvm.asan.globals = !{!3}
+!llvm.module.flags = !{!6, !7, !8}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2, nameTableKind: None)
+!1 = !DIFile(filename: "foo.c", directory: "/")
+!2 = !{}
+!3 = !{[1 x i32] addrspace(42)* @a, !4, !"a", i1 false, i1 false}
+!4 = !{!"foo.c", i32 1, i32 17}
+!6 = !{i32 2, !"Dwarf Version", i32 4}
+!7 = !{i32 2, !"Debug Info Version", i32 3}
+!8 = !{i32 1, !"wchar_size", i32 4}