PPC/s390: Add missing calls to `Unreachable`.

Port df748fc0

R=georgia.kouveli@arm.com, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: I3ae962a6c6f20c945c788e9ff512a3b02aff4754
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3331275Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#78342}

src/builtins/ppc/builtins-ppc.cc

@@ -524,6 +524,7 @@ void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {
   FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
   __ push(r4);
   __ CallRuntime(Runtime::kThrowConstructedNonConstructable);
+  __ Trap();  // Unreachable.
 }
 
 namespace {
@@ -2045,6 +2046,7 @@ void Builtins::Generate_CallOrConstructForwardVarargs(MacroAssembler* masm,
       __ EnterFrame(StackFrame::INTERNAL);
       __ Push(r6);
       __ CallRuntime(Runtime::kThrowNotConstructor);
+      __ Trap();  // Unreachable.
     }
     __ bind(&new_target_constructor);
   }
@@ -2209,6 +2211,7 @@ void Builtins::Generate_CallFunction(MacroAssembler* masm,
     FrameAndConstantPoolScope frame(masm, StackFrame::INTERNAL);
     __ push(r4);
     __ CallRuntime(Runtime::kThrowConstructorNonCallableError);
+    __ Trap();  // Unreachable.
   }
 }
 
@@ -2367,6 +2370,7 @@ void Builtins::Generate_Call(MacroAssembler* masm, ConvertReceiverMode mode) {
     FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
     __ Push(target);
     __ CallRuntime(Runtime::kThrowCalledNonCallable);
+    __ Trap();  // Unreachable.
   }
 
   // 4. The function is a "classConstructor", need to raise an exception.

src/builtins/s390/builtins-s390.cc

@@ -752,6 +752,7 @@ void Builtins::Generate_ConstructedNonConstructable(MacroAssembler* masm) {
   FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
   __ push(r3);
   __ CallRuntime(Runtime::kThrowConstructedNonConstructable);
+  __ Trap();  // Unreachable.
 }
 
 namespace {
@@ -2476,6 +2477,7 @@ void Builtins::Generate_CallOrConstructForwardVarargs(MacroAssembler* masm,
       __ EnterFrame(StackFrame::INTERNAL);
       __ Push(r5);
       __ CallRuntime(Runtime::kThrowNotConstructor);
+      __ Trap();  // Unreachable.
     }
     __ bind(&new_target_constructor);
   }
@@ -2641,6 +2643,7 @@ void Builtins::Generate_CallFunction(MacroAssembler* masm,
     FrameAndConstantPoolScope frame(masm, StackFrame::INTERNAL);
     __ push(r3);
     __ CallRuntime(Runtime::kThrowConstructorNonCallableError);
+    __ Trap();  // Unreachable.
   }
 }