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JULY 29, 2026
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Optimised tree expression check moved to a numbered definition.

A tree expression check for non-negativity is moved for better symbol lookup.

The tree_expr_nonnegative_p function, used for checking if a tree expression is non-negative, has been moved to a numbered alias (tree_expr_nonnegative_p@1). This change simplifies pattern matching and symbol resolution within the compiler’s internal representation, as indicated by PR tree-optimization/126087.

In Details

In the GCC tree-optimization subsystem, this commit refactors the match.pd file by re-establishing tree_expr_nonnegative_p under the numbered pattern tree_expr_nonnegative_p@1. This change is part of ongoing efforts to simplify pattern matching definitions and improve the lookup of predicates used in various optimization passes. It was bootstrapped and tested on x86_64-pc-linux-gnu.

For Context
tree
GCC's internal representation of code, structured as a parse tree where nodes represent expressions, statements, and declarations.
pattern matching
A technique used in compilers to find and manipulate structures within the intermediate representation (IR) of code. This is crucial for optimizations and code generation.
symbol resolution
The process of associating symbolic names in a program with their corresponding memory addresses or definitions. In GCC, this is related to how internal functions and data structures are identified and accessed.
compiler pass
A stage in the compilation process where the compiler performs specific transformations or analyses on the intermediate representation of the code.
Filed Under: matchoptimizationtree