[llvm] [SelectionDAG] Add support to filter SelectionDAG dumps during ISel by function names (PR #72696)

[Min-Yih Hsu via llvm-commits]

================
@@ -180,6 +182,15 @@ static const bool ViewDAGCombine1 = false, ViewLegalizeTypesDAGs = false,
                   ViewSchedDAGs = false, ViewSUnitDAGs = false;
 #endif
 
+#define ISEL_DUMP(F, X)                                                        \
+  do {                                                                         \
+    if (llvm::DebugFlag && (isCurrentDebugType(DEBUG_TYPE) ||                  \
+                            (isCurrentDebugType(ISEL_DUMP_DEBUG_TYPE) &&       \
+                             isFunctionInPrintList(F)))) {                     \
----------------
mshockwave wrote:

Done. Now it stores the filter result in a class member variable of `SelectionDAGISel`. Interesting side note: `isCurrentDebugType`, which is used by `LLVM_DUMP`, actually does a linear search to filter debug types every time it's called. But I guess the size of `-debug-only` is not big so it's fine for majority of the time.

https://github.com/llvm/llvm-project/pull/72696