[NewPM][Sancov] Create the Sancov Pass after building the pipelines

We're running into linker errors from missing sancov sections:

```
ld.lld: error: relocation refers to a discarded section: __sancov_guards
>>> defined in user-arm64-ubsan-sancov-full.shlib/obj/third_party/ulib/scudo/scudo.wrappers_c.cc.o
>>> referenced by common.h:26 (../../zircon/third_party/ulib/scudo/common.h:26)
... many other references
```

I believe this is due to a pass in the default pipeline that somehow discards
these sections. The ModuleSanitizerCoveragePass was initially added at the
start of the pipeline. This now adds it to the end of the pipeline for
optimized and unoptimized builds.

Differential Revision: https://reviews.llvm.org/D67323

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@371326 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/BackendUtil.cpp b/lib/CodeGen/BackendUtil.cpp
index 4a2f298d4b210d0dfbadcdbceba4dedb52aaf79b..251b1fce6d85e2458940843bb0719dd5b0b58e7b 100644 (file)
--- a/lib/CodeGen/BackendUtil.cpp
+++ b/lib/CodeGen/BackendUtil.cpp
@@ -1149,16 +1149,6 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
             EntryExitInstrumenterPass(/*PostInlining=*/false)));
       });
 
-      if (CodeGenOpts.SanitizeCoverageType ||
-          CodeGenOpts.SanitizeCoverageIndirectCalls ||
-          CodeGenOpts.SanitizeCoverageTraceCmp) {
-        auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
-        PB.registerPipelineStartEPCallback(
-            [SancovOpts](ModulePassManager &MPM) {
-              MPM.addPass(ModuleSanitizerCoveragePass(SancovOpts));
-            });
-      }
-
       // Register callbacks to schedule sanitizer passes at the appropriate part of
       // the pipeline.
       // FIXME: either handle asan/the remaining sanitizers or error out
@@ -1226,6 +1216,13 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
       }
     }
 
+    if (CodeGenOpts.SanitizeCoverageType ||
+        CodeGenOpts.SanitizeCoverageIndirectCalls ||
+        CodeGenOpts.SanitizeCoverageTraceCmp) {
+      auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
+      MPM.addPass(ModuleSanitizerCoveragePass(SancovOpts));
+    }
+
     if (LangOpts.Sanitize.has(SanitizerKind::HWAddress)) {
       bool Recover = CodeGenOpts.SanitizeRecover.has(SanitizerKind::HWAddress);
       MPM.addPass(HWAddressSanitizerPass(
@@ -1237,13 +1234,6 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
     }
 
     if (CodeGenOpts.OptimizationLevel == 0) {
-      if (CodeGenOpts.SanitizeCoverageType ||
-          CodeGenOpts.SanitizeCoverageIndirectCalls ||
-          CodeGenOpts.SanitizeCoverageTraceCmp) {
-        auto SancovOpts = getSancovOptsFromCGOpts(CodeGenOpts);
-        MPM.addPass(ModuleSanitizerCoveragePass(SancovOpts));
-      }
-
       addSanitizersAtO0(MPM, TargetTriple, LangOpts, CodeGenOpts);
     }
   }