[wasm] Remove default implementation for unknown architectures

The jump table assembler is implemented on all architectures now, so
remove the default code. It would be untested otherwise.

R=mstarzinger@chromium.org

Change-Id: I45e42fc04ebb3bb07d975648b1498e2ea4e757d4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1796328
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63682}

src/wasm/jump-table-assembler.cc

@@ -240,19 +240,7 @@ void JumpTableAssembler::NopBytes(int bytes) {
 }
 
 #else
-void JumpTableAssembler::EmitLazyCompileJumpSlot(uint32_t func_index,
-                                                 Address lazy_compile_target) {
-  UNIMPLEMENTED();
-}
-
-void JumpTableAssembler::EmitJumpSlot(Address target) { UNIMPLEMENTED(); }
-
-void JumpTableAssembler::EmitFarJumpSlot(Address target) { UNIMPLEMENTED(); }
-
-void JumpTableAssembler::NopBytes(int bytes) {
-  DCHECK_LE(0, bytes);
-  UNIMPLEMENTED();
-}
+#error Unknown architecture.
 #endif
 
 }  // namespace wasm

src/wasm/jump-table-assembler.h

@@ -201,10 +201,7 @@ class V8_EXPORT_PRIVATE JumpTableAssembler : public MacroAssembler {
   static constexpr int kFarJumpTableSlotSize = 6 * kInstrSize;
   static constexpr int kLazyCompileTableSlotSize = 8 * kInstrSize;
 #else
-  static constexpr int kJumpTableLineSize = 1;
-  static constexpr int kJumpTableSlotSize = 1;
-  static constexpr int kFarJumpTableSlotSize = 1;
-  static constexpr int kLazyCompileTableSlotSize = 1;
+#error Unknown architecture.
 #endif
 
   static constexpr int kJumpTableSlotsPerLine =