[sancov] specifying comdat for sancov constructors

Differential Revision: https://reviews.llvm.org/D29662

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294517 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
index ee5158fa1d594f4bf2997d5cce43c52aedee65da..76e5f8bd660faa987d6950409323944f8f581a89 100644 (file)
--- a/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
+++ b/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
@@ -382,7 +382,9 @@ bool SanitizerCoverageModule::runOnModule(Module &M) {
           {IRB.CreatePointerCast(SecStart, Int32PtrTy),
             IRB.CreatePointerCast(SecEnd, Int32PtrTy)});
 
-      appendToGlobalCtors(M, CtorFunc, SanCtorAndDtorPriority);
+      // Use comdat to dedup CtorFunc.
+      CtorFunc->setComdat(M.getOrInsertComdat(SanCovModuleCtorName));
+      appendToGlobalCtors(M, CtorFunc, SanCtorAndDtorPriority, CtorFunc);
     }
   } else if (!Options.TracePC) {
     Function *CtorFunc;

diff --git a/test/Instrumentation/SanitizerCoverage/coverage.ll b/test/Instrumentation/SanitizerCoverage/coverage.ll
index 9dceceb2eefa4e939b9d6bb0f5ece1d88bf177a9..6b2401b8581d9ec787b2751d3481b5fe23d7259e 100644 (file)
--- a/test/Instrumentation/SanitizerCoverage/coverage.ll
+++ b/test/Instrumentation/SanitizerCoverage/coverage.ll
@@ -7,7 +7,7 @@
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=3 -sanitizer-coverage-block-threshold=10 -S | FileCheck %s --check-prefix=CHECK3
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=4 -S | FileCheck %s --check-prefix=CHECK4
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=4 -sanitizer-coverage-trace-pc  -S | FileCheck %s --check-prefix=CHECK_TRACE_PC
-; RUN: opt < %s -sancov -sanitizer-coverage-level=4 -sanitizer-coverage-trace-pc-guard  -S | FileCheck %s --check-prefix=CHECK_TRACE_PC
+; RUN: opt < %s -sancov -sanitizer-coverage-level=4 -sanitizer-coverage-trace-pc-guard  -S | FileCheck %s --check-prefix=CHECK_TRACE_PC_GUARD
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=3 -sanitizer-coverage-8bit-counters=1  -S | FileCheck %s --check-prefix=CHECK-8BIT
 
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=2 -sanitizer-coverage-block-threshold=10 \
@@ -131,6 +131,18 @@ entry:
 ; CHECK_TRACE_PC: call void @__sanitizer_cov_trace_pc_indir
 ; CHECK_TRACE_PC: ret void
 
+; CHECK_TRACE_PC_GUARD-LABEL: define void @foo
+; CHECK_TRACE_PC_GUARD: call void @__sanitizer_cov_trace_pc
+; CHECK_TRACE_PC_GUARD: call void asm sideeffect "", ""()
+; CHECK_TRACE_PC_GUARD: ret void
+
+; CHECK_TRACE_PC_GUARD-LABEL: define void @CallViaVptr
+; CHECK_TRACE_PC_GUARD: call void @__sanitizer_cov_trace_pc_indir
+; CHECK_TRACE_PC_GUARD: call void @__sanitizer_cov_trace_pc_indir
+; CHECK_TRACE_PC_GUARD: ret void
+
+; CHECK_TRACE_PC_GUARD-LABEL: define internal void @sancov.module_ctor() comdat
+
 define void @call_unreachable() uwtable sanitize_address {
 entry:
   unreachable