[sancov] save entry block from pruning (it is always full dominator)

llvm-svn: 265168

diff --git a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
index 12fdfbd..1fac003 100644 (file)
--- a/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
+++ b/llvm/lib/Transforms/Instrumentation/SanitizerCoverage.cpp
@@ -342,9 +342,9 @@ static bool isFullPostDominator(const BasicBlock *BB,
   return true;
 }
 
-static bool shouldInstrumentBlock(const BasicBlock *BB, const DominatorTree *DT,
+static bool shouldInstrumentBlock(const Function& F, const BasicBlock *BB, const DominatorTree *DT,
                                   const PostDominatorTree *PDT) {
-  if (!ClPruneBlocks)
+  if (!ClPruneBlocks || &F.getEntryBlock() == BB)
     return true;
 
   return !(isFullDominator(BB, DT) || isFullPostDominator(BB, PDT));
@@ -374,7 +374,7 @@ bool SanitizerCoverageModule::runOnFunction(Function &F) {
       &getAnalysis<PostDominatorTreeWrapperPass>(F).getPostDomTree();
 
   for (auto &BB : F) {
-    if (shouldInstrumentBlock(&BB, DT, PDT))
+    if (shouldInstrumentBlock(F, &BB, DT, PDT))
       BlocksToInstrument.push_back(&BB);
     for (auto &Inst : BB) {
       if (Options.IndirectCalls) {

diff --git a/llvm/test/Instrumentation/SanitizerCoverage/coverage.ll b/llvm/test/Instrumentation/SanitizerCoverage/coverage.ll
index 71177eb..98f9a2e 100644 (file)
--- a/llvm/test/Instrumentation/SanitizerCoverage/coverage.ll
+++ b/llvm/test/Instrumentation/SanitizerCoverage/coverage.ll
@@ -13,7 +13,7 @@
 ; RUN:      -S | FileCheck %s --check-prefix=CHECK2
 ; RUN: opt < %s -sancov -sanitizer-coverage-level=2 -sanitizer-coverage-block-threshold=1 \
 ; RUN:      -S | FileCheck %s --check-prefix=CHECK_WITH_CHECK
-; RUN: opt < %s -sancov -sanitizer-coverage-level=2 -sanitizer-coverage-prune-blocks=1 -S | FileCheck %s --check-prefix=CHECKPRUNE
+; RUN: opt < %s -sancov -sanitizer-coverage-level=3 -sanitizer-coverage-prune-blocks=1 -S | FileCheck %s --check-prefix=CHECKPRUNE
 
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-unknown-linux-gnu"
@@ -138,8 +138,7 @@ entry:
 
 ; CHECKPRUNE-LABEL: define void @foo
 ; CHECKPRUNE: call void @__sanitizer_cov
-; CHECKPRUNE: call void asm sideeffect "", ""()
 ; CHECKPRUNE: call void @__sanitizer_cov
-; CHECKPRUNE: call void asm sideeffect "", ""()
+; CHECKPRUNE: call void @__sanitizer_cov
 ; CHECKPRUNE-NOT: call void @__sanitizer_cov
 ; CHECKPRUNE: ret void