diff options
Diffstat (limited to 'frontend/arm_utils.s')
| -rw-r--r-- | frontend/arm_utils.s | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/frontend/arm_utils.s b/frontend/arm_utils.s index 4e561f9..d131923 100644 --- a/frontend/arm_utils.s +++ b/frontend/arm_utils.s @@ -15,7 +15,8 @@ bgr555_to_rgb565: mov r3, #0x07c0 vdup.16 q15, r3 - sub r2, r2, #64 + subs r2, r2, #64 + blt btr16_end64 0: vldmia r1!, {q0-q3} vshl.u16 q4, q0, #11 @@ -38,20 +39,36 @@ bgr555_to_rgb565: subs r2, r2, #64 bge 0b +btr16_end64: adds r2, r2, #64 bxeq lr + subs r2, r2, #16 + blt btr16_end16 - @ handle the remainder + @ handle the remainder (reasonably rare) 0: - vld1.16 {q0}, [r1, :64]! + vld1.16 {q0}, [r1]! vshl.u16 q1, q0, #11 vshl.u16 q2, q0, #1 vsri.u16 q1, q0, #10 vbit q1, q2, q15 subs r2, r2, #16 - vst1.16 {q1}, [r0, :64]! - bgt 0b + vst1.16 {q1}, [r0]! + bge 0b +btr16_end16: + adds r2, r2, #16 + bxeq lr + subs r2, r2, #8 + bxlt lr + + @ very rare + vld1.16 d0, [r1]! + vshl.u16 d1, d0, #11 + vshl.u16 d2, d0, #1 + vsri.u16 d1, d0, #10 + vbit d1, d2, d30 + vst1.16 d1, [r0]! bx lr |