ppc:[liftoff] implement checking functions

Change-Id: I1efa3969ee07deca1dfa33f730f46a1067c12d73
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3152753Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/main@{#76768}

src/wasm/baseline/ppc/liftoff-assembler-ppc.h

@@ -2367,15 +2367,18 @@ void LiftoffAssembler::emit_i8x16_add_sat_u(LiftoffRegister dst,
 }
 
 void LiftoffAssembler::StackCheck(Label* ool_code, Register limit_address) {
-  bailout(kUnsupportedArchitecture, "StackCheck");
+  LoadU64(limit_address, MemOperand(limit_address), r0);
+  CmpU64(sp, limit_address);
+  ble(ool_code);
 }
 
 void LiftoffAssembler::CallTrapCallbackForTesting() {
-  bailout(kUnsupportedArchitecture, "CallTrapCallbackForTesting");
+  PrepareCallCFunction(0, 0, ip);
+  CallCFunction(ExternalReference::wasm_call_trap_callback_for_testing(), 0);
 }
 
 void LiftoffAssembler::AssertUnreachable(AbortReason reason) {
-  bailout(kUnsupportedArchitecture, "AssertUnreachable");
+  if (FLAG_debug_code) Abort(reason);
 }
 
 void LiftoffAssembler::PushRegisters(LiftoffRegList regs) {