[compiler] Compute dominator tree for tests

The dominator tree is usually computed as part of scheduling (in
{Scheduler::ComputeSchedule}). For tests it was missing, leading to
DCHECK errors in the mid-tier register allocator, which uses the
dominator tree.

R=mslekova@chromium.org

Bug: v8:12330
Change-Id: I02bc8dee3aecb6a1613fa1d07d3aae85cd28de17
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3245114Reviewed-by: Maya Lekova <mslekova@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77543}

src/compiler/raw-machine-assembler.cc

@@ -95,6 +95,7 @@ Schedule* RawMachineAssembler::ExportForTest() {
   }
   schedule_->EnsureCFGWellFormedness();
   Scheduler::ComputeSpecialRPO(zone(), schedule_);
+  Scheduler::GenerateDominatorTree(schedule_);
   schedule_->PropagateDeferredMark();
   if (FLAG_trace_turbo_scheduler) {
     PrintF("--- EDGE SPLIT AND PROPAGATED DEFERRED SCHEDULE ------------\n");

test/cctest/compiler/test-run-machops.cc

@@ -18,6 +18,7 @@
 #include "test/cctest/cctest.h"
 #include "test/cctest/compiler/codegen-tester.h"
 #include "test/cctest/compiler/value-helper.h"
+#include "test/common/flag-utils.h"
 
 namespace v8 {
 namespace internal {
@@ -7297,6 +7298,18 @@ TEST(Regression738952) {
   CHECK_EQ(sentinel, m.Call());
 }
 
+#if V8_TARGET_ARCH_64_BIT
+TEST(Regression12330) {
+  FLAG_SCOPE(turbo_force_mid_tier_regalloc);
+
+  RawMachineAssemblerTester<int32_t> m(MachineType::Int64());
+  Node* add = m.Int64SubWithOverflow(m.Int64Constant(0), m.Parameter(0));
+  Node* ovf = m.Projection(1, add);
+  m.Return(ovf);
+  m.GenerateCode();
+}
+#endif  // V8_TARGET_ARCH_64_BIT
+
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8