[UBsan] add -fsanitize-handler-preserve-all-regs flag

clang/include/clang/Basic/CodeGenOptions.def

@@ -270,6 +270,8 @@ CODEGENOPT(SanitizeMemoryUseAfterDtor, 1, 0, Benign) ///< Enable use-after-delet
 CODEGENOPT(SanitizeCfiCrossDso, 1, 0, Benign) ///< Enable cross-dso support in CFI.
 CODEGENOPT(SanitizeMinimalRuntime, 1, 0, Benign) ///< Use "_minimal" sanitizer runtime for
                                                  ///< diagnostics.
+CODEGENOPT(SanitizeHandlerPreserveAllRegs, 1, 0, Benign) ///< Use "_preserve" sanitizer runtime for
+                                                 ///< diagnostics.
 CODEGENOPT(SanitizeCfiICallGeneralizePointers, 1, 0, Benign) ///< Generalize pointer types in
                                                              ///< CFI icall function signatures
 CODEGENOPT(SanitizeCfiICallNormalizeIntegers, 1, 0, Benign) ///< Normalize integer types in

clang/include/clang/Driver/SanitizerArgs.h

@@ -67,6 +67,7 @@ class SanitizerArgs {
   bool TsanFuncEntryExit = true;
   bool TsanAtomics = true;
   bool MinimalRuntime = false;
+  bool HandlerPreserveAllRegs = false;
   // True if cross-dso CFI support if provided by the system (i.e. Android).
   bool ImplicitCfiRuntime = false;
   bool NeedsMemProfRt = false;

clang/include/clang/Options/Options.td

@@ -2660,6 +2660,15 @@ defm sanitize_minimal_runtime : BoolOption<"f", "sanitize-minimal-runtime",
   PosFlag<SetTrue>,
   NegFlag<SetFalse>>,
   Group<f_clang_Group>;
+defm sanitize_handler_preserve_all_regs
+    : BoolOption<
+          "f", "sanitize-handler-preserve-all-regs",
+          CodeGenOpts<"SanitizeHandlerPreserveAllRegs">, DefaultFalse,
+          PosFlag<SetTrue, [], [],
+                  "Enable handlers with preserve_all calling convention">,
+          NegFlag<SetFalse, [], [],
+                  "Disable handlers with preserve_all calling convention">>,
+      Group<f_clang_Group>;
 def fsanitize_link_runtime : Flag<["-"], "fsanitize-link-runtime">,
                            Group<f_clang_Group>;
 def fno_sanitize_link_runtime : Flag<["-"], "fno-sanitize-link-runtime">,

clang/lib/Driver/SanitizerArgs.cpp

@@ -423,6 +423,10 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
   MinimalRuntime =
       Args.hasFlag(options::OPT_fsanitize_minimal_runtime,
                    options::OPT_fno_sanitize_minimal_runtime, MinimalRuntime);
+  HandlerPreserveAllRegs =
+      Args.hasFlag(options::OPT_fsanitize_handler_preserve_all_regs,
+                   options::OPT_fno_sanitize_handler_preserve_all_regs,
+                   HandlerPreserveAllRegs);
 
   // The object size sanitizer should not be enabled at -O0.
   Arg *OptLevel = Args.getLastArg(options::OPT_O_Group);
@@ -1469,6 +1473,9 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
   if (MinimalRuntime)
     CmdArgs.push_back("-fsanitize-minimal-runtime");
 
+  if (HandlerPreserveAllRegs)
+    CmdArgs.push_back("-fsanitize-handler-preserve-all-regs");
+
   if (AsanFieldPadding)
     CmdArgs.push_back(Args.MakeArgString("-fsanitize-address-field-padding=" +
                                          Twine(AsanFieldPadding)));

clang/test/Driver/fsanitize.c

@@ -984,6 +984,11 @@
 // CHECK-UBSAN-MINIMAL: "-fsanitize={{((signed-integer-overflow|integer-divide-by-zero|shift-base|shift-exponent|unreachable|return|vla-bound|alignment|null|pointer-overflow|float-cast-overflow|array-bounds|enum|bool|builtin|returns-nonnull-attribute|nonnull-attribute|function),?){18}"}}
 // CHECK-UBSAN-MINIMAL: "-fsanitize-minimal-runtime"
 
+// RUN: %clang --target=x86_64-linux-gnu -fsanitize=undefined -fsanitize-minimal-runtime -fsanitize-handler-preserve-all-regs %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-UBSAN-MINIMAL-PRESERVE
+// CHECK-UBSAN-MINIMAL-PRESERVE: "-fsanitize={{((signed-integer-overflow|integer-divide-by-zero|shift-base|shift-exponent|unreachable|return|vla-bound|alignment|null|pointer-overflow|float-cast-overflow|array-bounds|enum|bool|builtin|returns-nonnull-attribute|nonnull-attribute|function),?){18}"}}
+// CHECK-UBSAN-MINIMAL-PRESERVE: "-fsanitize-minimal-runtime"
+// CHECK-UBSAN-MINIMAL-PRESERVE: "-fsanitize-handler-preserve-all-regs
+
 // RUN: %clang --target=x86_64-linux-gnu -fsanitize=integer -fsanitize-trap=integer %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-INTSAN-TRAP
 // CHECK-INTSAN-TRAP: "-fsanitize-trap=integer-divide-by-zero,shift-base,shift-exponent,signed-integer-overflow,unsigned-integer-overflow,unsigned-shift-base,implicit-unsigned-integer-truncation,implicit-signed-integer-truncation,implicit-integer-sign-change"