[OpenCL] Add missing -cl-no-signed-zeros option into driver

[ashi1]

Summary

Add OCL option -cl-no-signed-zeros to driver options.

Also added to opencl.cl testcases.

[yaxunl]

I think you also need to set Opts.NoSignedZeros in CompilerInvocation.cpp.

[ashi1]

Revised base on Sam's comments.

Added no-signed-zeros as an attribute no-signed-zeros-fp-math.
Added a test for no-signed-zeros-fp-math.

[yaxunl]

LGTM. Thanks.

[Anastasia]

LGTM! Thanks!

include/clang/Driver/Options.td

   HelpText<"OpenCL only. Sets -cl-finite-math-only and -cl-unsafe-math-optimizations, and defines __FAST_RELAXED_MATH__.">;
 def cl_mad_enable : Flag<["-"], "cl-mad-enable">, Group<opencl_Group>, Flags<[CC1Option]>,
   HelpText<"OpenCL only. Allow use of less precise MAD computations in the generated binary.">;
+def cl_no_signed_zeros : Flag<["-"], "cl-no-signed-zeros">, Group<opencl_Group>, Flags<[CC1Option]>,
+  HelpText<"OpenCL only. Allow use of less precise no signed zeros computations in the generated binary.">;
 def cl_std_EQ : Joined<["-"], "cl-std=">, Group<opencl_Group>, Flags<[CC1Option]>,
   HelpText<"OpenCL language standard to compile for.">;
 def cl_denorms_are_zero : Flag<["-"], "cl-denorms-are-zero">, Group<opencl_Group>, Flags<[CC1Option]>,

lib/CodeGen/CGCall.cpp

                            llvm::toStringRef(CodeGenOpts.SoftFloat));
     FuncAttrs.addAttribute("stack-protector-buffer-size",
                            llvm::utostr(CodeGenOpts.SSPBufferSize));
+    FuncAttrs.addAttribute("no-signed-zeros-fp-math",
+                           llvm::toStringRef(CodeGenOpts.NoSignedZeros));
 
     if (CodeGenOpts.StackRealignment)
       FuncAttrs.addAttribute("stackrealign");

lib/Driver/Tools.cpp

   if (Args.getLastArg(options::OPT_cl_mad_enable)) {
     CmdArgs.push_back("-cl-mad-enable");
   }
+  if (Args.getLastArg(options::OPT_cl_no_signed_zeros)) {
+    CmdArgs.push_back("-cl-no-signed-zeros");
+  }
   if (Arg *A = Args.getLastArg(options::OPT_cl_std_EQ)) {
     std::string CLStdStr = "-cl-std=";
     CLStdStr += A->getValue();

lib/Frontend/CompilerInvocation.cpp

                        Args.hasArg(OPT_cl_unsafe_math_optimizations) ||
                        Args.hasArg(OPT_cl_finite_math_only) ||
                        Args.hasArg(OPT_cl_fast_relaxed_math));
-  Opts.NoSignedZeros = Args.hasArg(OPT_fno_signed_zeros);
+  Opts.NoSignedZeros = (Args.hasArg(OPT_fno_signed_zeros) ||
+                        Args.hasArg(OPT_cl_no_signed_zeros));
   Opts.ReciprocalMath = Args.hasArg(OPT_freciprocal_math);
   Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss);
   Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option);

test/CodeGenOpenCL/no-signed-zeros.cl

+// RUN: %clang_cc1 %s -emit-llvm -o - | FileCheck %s -check-prefix=NORMAL
+// RUN: %clang_cc1 %s -emit-llvm -cl-no-signed-zeros -o - | FileCheck %s -check-prefix=NO-SIGNED-ZEROS
+
+float signedzeros(float a) {
+  return a;
+}
+
+// CHECK: attributes
+// NORMAL: "no-signed-zeros-fp-math"="false"
+// NO-SIGNED-ZEROS: "no-signed-zeros-fp-math"="true"

test/Driver/opencl.cl

 // RUN: %clang -S -### -cl-unsafe-math-optimizations %s | FileCheck --check-prefix=CHECK-UNSAFE-MATH-OPT %s
 // RUN: %clang -S -### -cl-fast-relaxed-math %s | FileCheck --check-prefix=CHECK-FAST-RELAXED-MATH %s
 // RUN: %clang -S -### -cl-mad-enable %s | FileCheck --check-prefix=CHECK-MAD-ENABLE %s
+// RUN: %clang -S -### -cl-no-signed-zeros %s | FileCheck --check-prefix=CHECK-NO-SIGNED-ZEROS %s
 // RUN: %clang -S -### -cl-denorms-are-zero %s | FileCheck --check-prefix=CHECK-DENORMS-ARE-ZERO %s
 // RUN: not %clang_cc1 -cl-std=c99 -DOPENCL %s 2>&1 | FileCheck --check-prefix=CHECK-C99 %s
 // RUN: not %clang_cc1 -cl-std=invalid -DOPENCL %s 2>&1 | FileCheck --check-prefix=CHECK-INVALID %s

 // CHECK-UNSAFE-MATH-OPT: .*clang.* "-cc1" .* "-cl-unsafe-math-optimizations"
 // CHECK-FAST-RELAXED-MATH: .*clang.* "-cc1" .* "-cl-fast-relaxed-math"
 // CHECK-MAD-ENABLE: .*clang.* "-cc1" .* "-cl-mad-enable"
+// CHECK-NO-SIGNED-ZEROS: .*clang.* "-cc1" .* "-cl-no-signed-zeros"
 // CHECK-DENORMS-ARE-ZERO: .*clang.* "-cc1" .* "-cl-denorms-are-zero"
 // CHECK-C99: error: invalid argument '-cl-std=c99' not allowed with 'OpenCL'
 // CHECK-INVALID: error: invalid value 'invalid' in '-cl-std=invalid'