[PATCH (6/7)] More widening multiply-and-accumulate pattern matching

Andrew Stubbs andrew.stubbs@gmail.com
Tue Jun 28 15:49:00 GMT 2011

On 23/06/11 15:42, Andrew Stubbs wrote:
> This patch fixes the case where widening multiply-and-accumulate were
> not recognised because the multiplication itself is not actually widening.
> This can happen when you have "DI + SI * SI" - the multiplication will
> be done in SImode as a non-widening multiply, and it's only the final
> accumulate step that is widening.
> This was not recognised for two reasons:
> 1. is_widening_mult_p inferred the output type from the multiply
> statement, which in not useful in this case.
> 2. The inputs to the multiply instruction may not have been converted at
> all (because they're not being widened), so the pattern match failed.
> The patch fixes these issues by making the output type explicit, and by
> permitting unconverted inputs (the types are still checked, so this is
> safe).
> OK?

This update fixes Janis' testsuite issue.

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