[wasm] Enable loop unrolling

Additionally, reduce the maximum times a loop can be unrolled to 5.

Bug: v8:11298
Change-Id: Ia3cc5955c91e70abf388e08bdc37aba998b34b93
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2953297Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75118}

src/compiler/loop-unrolling.h

@@ -18,7 +18,7 @@ namespace internal {
 namespace compiler {
 
 static constexpr uint32_t kMaximumUnnestedSize = 50;
-static constexpr uint32_t kMaximumUnrollingCount = 7;
+static constexpr uint32_t kMaximumUnrollingCount = 5;
 
 // A simple heuristic to decide how many times to unroll a loop. Favors small
 // and deeply nested loops.

src/flags/flag-definitions.h

@@ -1018,8 +1018,8 @@ DEFINE_BOOL(wasm_stack_checks, true,
 DEFINE_BOOL(wasm_math_intrinsics, true,
             "intrinsify some Math imports into wasm")
 
-DEFINE_BOOL(wasm_loop_unrolling, false,
-            "enable loop unrolling for wasm functions (experimental)")
+DEFINE_BOOL(wasm_loop_unrolling, true,
+            "enable loop unrolling for wasm functions")
 DEFINE_BOOL(wasm_trap_handler, true,
             "use signal handlers to catch out of bounds memory access in wasm"
             " (currently Linux x86_64 only)")