[llvm] [VPlan] Add hidden `-vplan-print-after-all` option (PR #175839)

[Andrei Elovikov via llvm-commits]

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@@ -33,27 +33,47 @@ class VPRecipeBuilder;
 struct VFRange;
 
 LLVM_ABI_FOR_TEST extern cl::opt<bool> VerifyEachVPlan;
+LLVM_ABI_FOR_TEST extern cl::opt<bool> PrintAfterEachVPlanPass;
 LLVM_ABI_FOR_TEST extern cl::opt<bool> EnableWideActiveLaneMask;
 
 struct VPlanTransforms {
-  /// Helper to run a VPlan transform \p Transform on \p VPlan, forwarding extra
-  /// arguments to the transform. Returns the boolean returned by the transform.
-  template <typename... ArgsTy>
-  static bool runPass(bool (*Transform)(VPlan &, ArgsTy...), VPlan &Plan,
-                      typename std::remove_reference<ArgsTy>::type &...Args) {
-    bool Res = Transform(Plan, Args...);
-    if (VerifyEachVPlan)
-      verifyVPlanIsValid(Plan);
-    return Res;
-  }
   /// Helper to run a VPlan transform \p Transform on \p VPlan, forwarding extra
   /// arguments to the transform.
-  template <typename... ArgsTy>
-  static void runPass(void (*Fn)(VPlan &, ArgsTy...), VPlan &Plan,
-                      typename std::remove_reference<ArgsTy>::type &...Args) {
-    Fn(Plan, Args...);
-    if (VerifyEachVPlan)
-      verifyVPlanIsValid(Plan);
+  template <auto Transform, bool DisableVerify = false, typename... ArgsTy>
+  static auto runPass(VPlan &Plan, ArgsTy &&...Args) {
+    using ResTy = decltype(Transform(Plan, std::forward<ArgsTy>(Args)...));
+    // Needs to be directly in `runPass` and not inside a lambda below:
+    constexpr StringRef PrettyFunc{LLVM_PRETTY_FUNCTION};
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eas wrote:

No, it won't, because `LLVM_PRETTY_FUNCTION` refers to the `runPass` helper, and `simplifyRecipes` is a template parameter for it. In the worst case, `LLVM_PRETTY_FUNCTION` would be just `__func__` that would only contain `runPass` without any of its template params.

https://github.com/llvm/llvm-project/pull/175839