Re: [PATCH] aarch64: Don't include vec_select high-half in SIMD multiply cost

2021-08-04 Thread Richard Sandiford via Gcc-patches
Jonathan Wright via Gcc-patches writes: > Hi, > > The Neon multiply/multiply-accumulate/multiply-subtract instructions > can select the top or bottom half of the operand registers. This > selection does not change the cost of the underlying instruction and > this should be reflected by the RTL cos

[PATCH] aarch64: Don't include vec_select high-half in SIMD multiply cost

2021-07-28 Thread Jonathan Wright via Gcc-patches
Hi, The Neon multiply/multiply-accumulate/multiply-subtract instructions can select the top or bottom half of the operand registers. This selection does not change the cost of the underlying instruction and this should be reflected by the RTL cost function. This patch adds RTL tree traversal in t