VC should produce debuggable kernels by default

This commit enables compilation of kernels that are suitable
for HW debug by default. BTI index zero is considered
reserved (for SIP surface access by the debugger).
Note, that to do a proper debug session one still has to
either inject breakpoint bits to the first instruction
of a kernel (This is enabled by "-g" currently) or to somehow
postpone kernel execution by other means (by passing extra
parameters to runtime or DCD).

Author: aparshin-intel

IGC/Options/include/igc/Options/VCInternalOptions.td

@@ -56,6 +56,9 @@ def stats_file : PlainSeparate<"stats-file">,
 def : PlainJoined<"stats-file=">, Alias<stats_file>,
   HelpText<"Alias for -stats-file">;
 
+def fdisable_debuggable_kernels : PlainFlag<"vc-disable-debuggable-kernels">,
+  HelpText<"Disable emission of debuggable kernels for legacy path">;
+
 def gpu_scope_fence : PlainFlag<"gpu-scope-fence-on-single-tile">,
   HelpText<"Allow the use of \"GPU\" fence scope on single-tile GPUs">;
 def flush_l3_for_global : PlainFlag<"flush-l3-for-global">,

IGC/VectorCompiler/include/vc/Driver/Driver.h

@@ -73,8 +73,9 @@ struct CompileOptions {
   bool NoVecDecomp = false;
   // -g
   bool ExtendedDebuggingSupport = false;
-  // emit kernels that can interact with debugger
-  bool EmitDebuggableKernels = false;
+  // emit kernels that can interact with debugger, can be disabled by
+  // -vc-disable-debuggable-kernels internal option
+  bool EmitDebuggableKernels = true;
   // -fno-jump-tables
   bool NoJumpTables = false;
   // -ftranslate-legacy-memory-intrinsics

IGC/VectorCompiler/include/vc/Support/BackendConfig.h

@@ -50,7 +50,7 @@ void initializeGenXBackendConfigPass(PassRegistry &PR);
 // configuration. Some values are default-initialized from cl options.
 struct GenXBackendOptions {
   // EmitDebuggable Kernels (allocate SIP Surface)
-  bool DebuggabilityEmitDebuggableKernels = false;
+  bool DebuggabilityEmitDebuggableKernels = true;
   // Legacy path requires kernel to reserve BTI=0
   bool DebuggabilityForLegacyPath = false;
   // Emit breakpoints at the start of each kernel

IGC/VectorCompiler/lib/Driver/Driver.cpp

@@ -619,10 +619,8 @@ static Error fillApiOptions(const opt::ArgList &ApiOptions,
 
   if (ApiOptions.hasArg(OPT_no_vector_decomposition))
     Opts.NoVecDecomp = true;
-  if (ApiOptions.hasArg(OPT_emit_debug)) {
+  if (ApiOptions.hasArg(OPT_emit_debug))
     Opts.ExtendedDebuggingSupport = true;
-    Opts.EmitDebuggableKernels = true;
-  }
   if (ApiOptions.hasArg(OPT_vc_fno_struct_splitting))
     Opts.DisableStructSplitting = true;
   if (ApiOptions.hasArg(OPT_vc_fno_jump_tables))
@@ -701,6 +699,8 @@ static Error fillInternalOptions(const opt::ArgList &InternalOptions,
     Opts.UseBindlessBuffers = true;
   if (InternalOptions.hasArg(OPT_emit_zebin_visa_sections))
     Opts.EmitZebinVisaSections = true;
+  if (InternalOptions.hasArg(OPT_fdisable_debuggable_kernels))
+    Opts.EmitDebuggableKernels = false;
 
   if (opt::Arg *A = InternalOptions.getLastArg(OPT_binary_format)) {
     StringRef Val = A->getValue();