Reimplement -fsanitize-recover family of flags.

Introduce the following -fsanitize-recover flags:
  - -fsanitize-recover=<list>: Enable recovery for selected checks or
      group of checks. It is forbidden to explicitly list unrecoverable
      sanitizers here (that is, "address", "unreachable", "return").
  - -fno-sanitize-recover=<list>: Disable recovery for selected checks or
     group of checks.
  - -f(no-)?sanitize-recover is now a synonym for
    -f(no-)?sanitize-recover=undefined,integer and will soon be deprecated.

These flags are parsed left to right, and mask of "recoverable"
sanitizer is updated accordingly, much like what we do for -fsanitize= flags.
-fsanitize= and -fsanitize-recover= flag families are independent.

CodeGen change: If there is a single UBSan handler function, responsible
for implementing multiple checks, which have different recoverable setting,
then we emit two handler calls instead of one:
the first one for the set of "unrecoverable" checks, another one - for
set of "recoverable" checks. If all checks implemented by a handler have the
same recoverability setting, then the generated code will be the same.

llvm-svn: 225719

1 files changed, 23 insertions, 13 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index d630b5b..0f6f01d 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -325,6 +325,21 @@ GenerateOptimizationRemarkRegex(DiagnosticsEngine &Diags, ArgList &Args,
   return Pattern;
 }
 
+static void parseSanitizerKinds(StringRef FlagName,
+                                const std::vector<std::string> &Sanitizers,
+                                DiagnosticsEngine &Diags, SanitizerSet &S) {
+  for (const auto &Sanitizer : Sanitizers) {
+    SanitizerKind K = llvm::StringSwitch<SanitizerKind>(Sanitizer)
+#define SANITIZER(NAME, ID) .Case(NAME, SanitizerKind::ID)
+#include "clang/Basic/Sanitizers.def"
+                          .Default(SanitizerKind::Unknown);
+    if (K == SanitizerKind::Unknown)
+      Diags.Report(diag::err_drv_invalid_value) << FlagName << Sanitizer;
+    else
+      S.set(K, true);
+  }
+}
+
 static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
                              DiagnosticsEngine &Diags,
                              const TargetOptions &TargetOpts) {
@@ -465,7 +480,6 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
 
   Opts.MainFileName = Args.getLastArgValue(OPT_main_file_name);
   Opts.VerifyModule = !Args.hasArg(OPT_disable_llvm_verifier);
-  Opts.SanitizeRecover = !Args.hasArg(OPT_fno_sanitize_recover);
 
   Opts.DisableGCov = Args.hasArg(OPT_test_coverage);
   Opts.EmitGcovArcs = Args.hasArg(OPT_femit_coverage_data);
@@ -596,6 +610,12 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
 
   Opts.RewriteMapFiles = Args.getAllArgValues(OPT_frewrite_map_file);
 
+  // Parse -fsanitize-recover= arguments.
+  // FIXME: Report unrecoverable sanitizers incorrectly specified here.
+  parseSanitizerKinds("-fsanitize-recover=",
+                      Args.getAllArgValues(OPT_fsanitize_recover_EQ), Diags,
+                      Opts.SanitizeRecover);
+
   return Success;
 }
 
@@ -1635,18 +1655,8 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   }
 
   // Parse -fsanitize= arguments.
-  std::vector<std::string> Sanitizers = Args.getAllArgValues(OPT_fsanitize_EQ);
-  for (const auto &Sanitizer : Sanitizers) {
-    SanitizerKind K = llvm::StringSwitch<SanitizerKind>(Sanitizer)
-#define SANITIZER(NAME, ID) .Case(NAME, SanitizerKind::ID)
-#include "clang/Basic/Sanitizers.def"
-        .Default(SanitizerKind::Unknown);
-    if (K == SanitizerKind::Unknown)
-      Diags.Report(diag::err_drv_invalid_value)
-        << "-fsanitize=" << Sanitizer;
-    else
-      Opts.Sanitize.set(K, true);
-  }
+  parseSanitizerKinds("-fsanitize=", Args.getAllArgValues(OPT_fsanitize_EQ),
+                      Diags, Opts.Sanitize);
   // -fsanitize-address-field-padding=N has to be a LangOpt, parse it here.
   Opts.SanitizeAddressFieldPadding =
       getLastArgIntValue(Args, OPT_fsanitize_address_field_padding, 0, Diags);