On 30/09/15 19:38, Jason Ekstrand wrote: > I'm not sure if this makes sense. I can see how it would be useful > (less information lost when going src_reg -> dst_reg -> src_reg). > However, it seems wrong to me to assume that dst_reg.abs or > dst_reg.negate means anything useful.
Hmm, true. FWIW, this commit didn't solve any bug on master, but one I had on my wip code, while porting some code from test_fs_cmod_propagation to a vec4 equivalent. The original code is this: bld.ADD(dest, src0, src1); dest.negate = true; bld.CMP(bld.null_reg_f(), dest, zero, BRW_CONDITIONAL_GE); That being translated without too much thinking to vec4 is something like: bld.ADD(dest, src0, src1); dest.negate = true; bld.CMP(bld.null_reg_f(), src_reg(dest), zero, BRW_CONDITIONAL_GE); That fails as src_reg doesn't copy the negate. I got misled by the original "dest.negate = true", without realizing that doesn't makes too much sense. It was just set to be used as a source on the following comparison. At this point the only advantage of using this patch is avoiding some lines with auxiliar vars like this: bld.ADD(dest, src0, src1); src_reg tmp = src_reg(dest); tmp.negate = true; bld.CMP(bld.null_reg_f(), tmp, zero, BRW_CONDITIONAL_GE); So I think that it would be better to forget this patch. Sorry for the noise. > Matt? > --Jason > > On Wed, Sep 30, 2015 at 10:32 AM, Alejandro Piñeiro > <apinhe...@igalia.com> wrote: >> --- >> src/mesa/drivers/dri/i965/brw_vec4.cpp | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp >> b/src/mesa/drivers/dri/i965/brw_vec4.cpp >> index c61b385..121e698 100644 >> --- a/src/mesa/drivers/dri/i965/brw_vec4.cpp >> +++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp >> @@ -139,6 +139,8 @@ src_reg::src_reg(const dst_reg ®) >> this->reladdr = reg.reladdr; >> this->fixed_hw_reg = reg.fixed_hw_reg; >> this->swizzle = brw_swizzle_for_mask(reg.writemask); >> + this->negate = reg.negate; >> + this->abs = reg.abs; >> } >> >> void >> @@ -204,6 +206,8 @@ dst_reg::dst_reg(const src_reg ®) >> this->writemask = brw_mask_for_swizzle(reg.swizzle); >> this->reladdr = reg.reladdr; >> this->fixed_hw_reg = reg.fixed_hw_reg; >> + this->abs = reg.abs; >> + this->negate = reg.negate; >> } >> >> bool >> -- >> 2.1.4 >> >> _______________________________________________ >> mesa-dev mailing list >> mesa-dev@lists.freedesktop.org >> http://lists.freedesktop.org/mailman/listinfo/mesa-dev -- Alejandro Piñeiro (apinhe...@igalia.com) _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
