On 9/20/26 12:16 PM, Kyrylo Tkachov wrote:
This is what this patch 1 is intended to address:
The RTL in your message is the pre-patch result. On targets with conditional
compares, expand_expr_real_gassign tries the generic conditional-compare
expander before normal binary expansion. Without this patch, it treats each
plain boolean as != 0, which sends the expression through the AArch64 CMP/CCMP
hooks.
This patch rejects the all-boolean candidate before that expander emits any
RTL. Expansion then falls through to the normal BIT_IOR_EXPR path. The initial
RTL after the patch contains an ior:SI, which produces orr w0, w0, w1. It
therefore starts with the same ordinary IOR form as the RISC-V expansion. Mixed
chains still use conditional compares.
Thanks for clarifying. I didn't realize there was some magic that
rerouted IOR into that conditional compare path, I thought was something
crazy in the aarch64 backend doing that.
Jeff
