[SYCL][Driver] Allow for -g0 to override default setting with -fintelfpga (#678)

When using -fintelfpga, -g is the default.  Allow for the user to specify a
-gN option on the command line to override.

Signed-off-by: Michael D Toguchi <michael.d.toguchi@intel.com>

Author: mdtoguchi

clang/lib/Driver/Driver.cpp

@@ -402,7 +402,11 @@ DerivedArgList *Driver::TranslateInputArgs(const InputArgList &Args) const {
   // Use of -fintelfpga implies -g and -MMD
   if (Args.hasArg(options::OPT_fintelfpga)) {
     DAL->AddFlagArg(0, Opts.getOption(options::OPT_MMD));
-    DAL->AddFlagArg(0, Opts.getOption(options::OPT_g_Flag));
+    // if any -gN option is provided, use that.
+    if (Arg *A = Args.getLastArg(options::OPT_gN_Group))
+      DAL->append(A);
+    else
+      DAL->AddFlagArg(0, Opts.getOption(options::OPT_g_Flag));
   }
 
 // Add a default value of -mlinker-version=, if one was given and the user

clang/test/Driver/sycl-offload-intelfpga.cpp

@@ -9,6 +9,11 @@
 // CHK-TOOLS-INTELFPGA: clang{{.*}} "-debug-info-kind=limited" {{.*}} "-dependency-file"
 // CHK-TOOLS-INTELFPGA: aoc{{.*}} "-dep-files={{.*}}"
 
+/// -fintelfpga implies -g but -g0 should override
+// RUN:   %clang++ -### -target x86_64-unknown-linux-gnu -g0 -fsycl -fintelfpga %s 2>&1 \
+// RUN:   | FileCheck -check-prefix=CHK-TOOLS-INTELFPGA-G0 %s
+// CHK-TOOLS-INTELFPGA-G0-NOT: clang{{.*}} "-debug-info-kind=limited"
+
 /// -fintelfpga -fsycl-link tests
 // RUN:  touch %t.o
 // RUN:  %clang++ -### -target x86_64-unknown-linux-gnu -fsycl -fintelfpga -fsycl-link %t.o 2>&1 \