10.03.2025 05:35, Chao Liu wrote:
Recently, when I was writing a RISCV test, I found that when VL is set to 0, the instruction should be nop, but when I tested it, I found that QEMU will treat all elements as tail elements, and in the case of VTA=1, write all elements to 1.After troubleshooting, it was found that the vext_vx_rm_1 function was called in the vext_vx_rm_2, and then the vext_set_elems_1s function was called to process the tail element, but only VSTART >= vl was checked in the vext_vx_rm_1 function, which caused the tail element to still be processed even if it was returned in advance. So I've made the following change: Put VSTART_CHECK_EARLY_EXIT(env) at the beginning of the vext_vx_rm_2 function, so that the VSTART register is checked correctly. Fixes: df4252b2ec ("target/riscv/vector_helpers: do early exit when vstart >= vl") Signed-off-by: Chao Liu <[email protected]> Reviewed-by: Daniel Henrique Barboza <[email protected]>
Is this a qemu-stable material (9.2)? Thanks, /mjt
