Zero operands produce a zero high and low product. One operands produce
a copy of the other operand and a zero or sign extension in the high
half.
Fold those cases during TCG optimization so wide-multiply idioms used by
target translators can collapse before code generation.
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20260520125139.13352-3-philmd@linaro.org>
c9349965ce