psx_gpu: fix mask set in blend_blocks variant

thanks to Exophase for help with coming up with this fix

diff --git a/plugins/gpu_neon/psx_gpu/psx_gpu_arm_neon.S b/plugins/gpu_neon/psx_gpu/psx_gpu_arm_neon.S
index 344331d..d8fb153 100644 (file)
--- a/plugins/gpu_neon/psx_gpu/psx_gpu_arm_neon.S
+++ b/plugins/gpu_neon/psx_gpu/psx_gpu_arm_neon.S
@@ -4280,6 +4280,7 @@ function(blend_blocks_textured_unblended_on)
   beq 1f
 
  0:
+  vorr.u16 pixels, pixels, msb_mask
   vorr.u16 draw_mask, draw_mask, write_mask
   vbif.u16 fb_pixels, pixels, draw_mask
   vst1.u16 { fb_pixels }, [ fb_ptr ]
@@ -4294,6 +4295,7 @@ function(blend_blocks_textured_unblended_on)
   bne 0b
  
  1:
+  vorr.u16 pixels, pixels, msb_mask
   vorr.u16 draw_mask, draw_mask, write_mask
   vbif.u16 fb_pixels, pixels, draw_mask
   vst1.u16 { fb_pixels }, [ fb_ptr ]