diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp index 310f3470dd7..9fc7ec7996c 100644 --- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp +++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp @@ -2469,9 +2469,24 @@ vec4_visitor::emit_scratch_write(vec4_instruction *inst, int base_offset) int reg_offset = base_offset + inst->dst.reg_offset; src_reg index = get_scratch_offset(inst, inst->dst.reladdr, reg_offset); - /* Create a temporary register to store *inst's result in. */ + /* Create a temporary register to store *inst's result in. + * + * We have to be careful in MOVing from our temporary result register in + * the scratch write. If we swizzle from channels of the temporary that + * weren't initialized, it will confuse live interval analysis, which will + * make spilling fail to make progress. + */ src_reg temp = src_reg(this, glsl_type::vec4_type); temp.type = inst->dst.type; + int first_writemask_chan = ffs(inst->dst.writemask) - 1; + int swizzles[4]; + for (int i = 0; i < 4; i++) + if (inst->dst.writemask & (1 << i)) + swizzles[i] = i; + else + swizzles[i] = first_writemask_chan; + temp.swizzle = BRW_SWIZZLE4(swizzles[0], swizzles[1], + swizzles[2], swizzles[3]); dst_reg dst = dst_reg(brw_writemask(brw_vec8_grf(0, 0), inst->dst.writemask)); |