[Lldb-commits] [lldb] [LLDB] Add AST node classes, functions, etc. for Data Inspection Lang… (PR #95738)

[Andy Hippo via lldb-commits]

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@@ -0,0 +1,165 @@
+(* LLDB Debug Expressions, a subset of C++ *)
+(* Insired by https://www.nongnu.org/hcb *)
+
+expression = assignment_expression ;
+
+assignment_expression = conditional_expression
+                        logical_or_expression assignment_operator assignment_expression ;
+
+assignment_operator = "="
+                    | "*="
+                    | "/="
+                    | "%="
+                    | "+="
+                    | "-="
+                    | ">>="
+                    | "<<="
+                    | "&="
+                    | "^="
+                    | "|=" ;
+
+conditional_expression = logical_or_expression
+                       | logical_or_expression "?" expression ":" assignment_expression ;
+
+logical_or_expression = logical_and_expression {"||" logical_and_expression} ;
+
+logical_and_expression = inclusive_or_expression {"&&" inclusive_or_expression} ;
+
+inclusive_or_expression = exclusive_or_expression {"|" exclusive_or_expression} ;
+
+exclusive_or_expression = and_expression {"^" and_expression} ;
+
+and_expression = equality_expression {"&" equality_expression} ;
+
+equality_expression = relational_expression {"==" relational_expression}
+                    | relational_expression {"!=" relational_expression} ;
+
+relational_expression = shift_expression {"<" shift_expression}
+                      | shift_expression {">" shift_expression}
+                      | shift_expression {"<=" shift_expression}
+                      | shift_expression {">=" shift_expression} ;
+
+shift_expression = additive_expression {"<<" additive_expression}
+                 | additive_expression {">>" additive_expression} ;
+
+additive_expression = multiplicative_expression {"+" multiplicative_expression}
+                    | multiplicative_expression {"-" multiplicative_expression} ;
+
+multiplicative_expression = cast_expression {"*" cast_expression}
+                          | cast_expression {"/" cast_expression}
+                          | cast_expression {"%" cast_expression} ;
+
+cast_expression = unary_expression
+                | "(" type_id ")" cast_expression ;
+
+unary_expression = postfix_expression
----------------
werat wrote:

It is pretty useful to be able to easily change the program state and afaik it's already possible with `expr` command. Generally other debugger allow this as well (e.g. Visual Studio), so I think it's a reasonable thing to do. However, for increments specifically there's a deeper reason here (and I would agree that they probably shouldn't be available for general use). See my big comment below for justification.

https://github.com/llvm/llvm-project/pull/95738