minor skvm cleanup

This is just minor little stuff I've been meaning to do,
with essentially no impact anywhere.

   - Add an easy-to-flip switch to disable the JIT.

   - Stop checking so carefully whether we hasJIT()
     in test_jit_and_interpreter().  This was helpful
     for making progress but now just gets in the way.

Change-Id: I08065ba1f42700f9d7d63f8303af357ec5fe11ae
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/302944
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Herb Derby <herb@google.com>
diff --git a/src/core/SkVM.h b/src/core/SkVM.h
index 262f1fe..96b54f4 100644
--- a/src/core/SkVM.h
+++ b/src/core/SkVM.h
@@ -23,6 +23,10 @@
     #define SKVM_LLVM
 #endif
 
+#if 0
+    #undef SKVM_JIT
+#endif
+
 namespace skvm {
 
     bool fma_supported();
diff --git a/tests/SkVMTest.cpp b/tests/SkVMTest.cpp
index 6bcb470..1a08915 100644
--- a/tests/SkVMTest.cpp
+++ b/tests/SkVMTest.cpp
@@ -34,16 +34,6 @@
 
 template <typename Fn>
 static void test_jit_and_interpreter(skvm::Program&& program, Fn&& test) {
-#if defined(SKVM_LLVM)
-    SkASSERT(program.hasJIT());
-#elif defined(SKVM_JIT) && defined(SK_CPU_X86)
-    SkASSERT(program.hasJIT() == SkCpu::Supports(SkCpu::HSW));
-#elif defined(SKVM_JIT)                         // eventually!
-    //SkASSERT(program.hasJIT());
-#else
-    SkASSERT(!program.hasJIT());
-#endif
-
     if (program.hasJIT()) {
         test((const skvm::Program&) program);
         program.dropJIT();