[llvm] [Tablegen] Add keywork `dump`. (PR #68793)

[Wang Pengcheng via llvm-commits]

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@@ -0,0 +1,46 @@
+// RUN: llvm-tblgen %s -o -  2>&1 >/dev/null | FileCheck %s
+
+// CHECK-LABEL: Debug message
+dump "Debug message";
+
+// CHECK-LABEL: The Value of A is:
+// CHECK-NEXT: a {     // A
+// CHECK-NEXT: string A = "some text";
+// CHECK-NEXT: dag X = (op op);
+// CHECK-NEXT: }
+def op;
+class A {
+  string A = "some text";
+  dag X =(op op);
+}
+def a : A;
+dump "The Value of A is: \n" # !repr(a);
+
+
+// CHECK-LABEL: b {     // A
+// CHECK-NEXT: string A = "some text";
+// CHECK-NEXT: dag X = (op op);
+// CHECK-NEXT: }
+def b : A;
+dump !repr(b) ;
+
+// CHECK-LABEL: got a pair of values ["some other text" : 12], and an empty record:
+// CHECK-NEXT: X {
+// CHECK-NEXT: }
+defvar value_A = "some other text";
+defvar value_B = 12;
+def X;
+dump "got a pair of values [" # !repr(value_A) # " : " # !repr(value_B) # "], " # "and an empty record:\n" # !repr(X);
+
+multiclass MC<dag s> {
+  dump "s = " # !repr(s);
+  dump "args[0] = " # !repr(!getdagarg<A>(s,0));
+  def A;
+}
+// CHECK-LABEL: note: s = (op a)
+// CHECK-NEXT: args[0] = a {        // A
+// CHECK-NEXT:   string A = "some text";
+// CHECK-NEXT: dag X = (op op);
+// CHECK-NEXT: }
+defm X : MC<(op a)>;
+
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wangpc-pp wrote:

Please add some tests for `dump`s in `foreach`, `class`, etc.

https://github.com/llvm/llvm-project/pull/68793