1 files changed, 96 insertions, 0 deletions
diff --git a/plugins/gpu_unai/gpu_inner_blend_arm.h b/plugins/gpu_unai/gpu_inner_blend_arm.h
new file mode 100644
index 0000000..4db105a
--- /dev/null
+++ b/plugins/gpu_unai/gpu_inner_blend_arm.h
@@ -0,0 +1,96 @@
+#ifndef _OP_BLEND_ARM_H_
+#define _OP_BLEND_ARM_H_
+
+////////////////////////////////////////////////////////////////////////////////
+// Blend bgr555 color in 'uSrc' (foreground) with bgr555 color
+//  in 'uDst' (background), returning resulting color.
+//
+// INPUT:
+//  'uSrc','uDst' input: -bbbbbgggggrrrrr
+//                       ^ bit 16
+// OUTPUT:
+//           u16 output: 0bbbbbgggggrrrrr
+//                       ^ bit 16
+// RETURNS:
+// Where '0' is zero-padding, and '-' is don't care
+////////////////////////////////////////////////////////////////////////////////
+template <int BLENDMODE, bool SKIP_USRC_MSB_MASK>
+GPU_INLINE u16 gpuBlendingARM(u16 uSrc, u16 uDst)
+{
+	// These use Blargg's bitwise modulo-clamping:
+	//  http://blargg.8bitalley.com/info/rgb_mixing.html
+	//  http://blargg.8bitalley.com/info/rgb_clamped_add.html
+	//  http://blargg.8bitalley.com/info/rgb_clamped_sub.html
+
+  
+	u16 mix;
+
+  asm ("bic %[uDst], %[uDst], #0x8000" : [uDst] "+r" (uDst));
+
+  if (BLENDMODE == 3) {
+    asm ("and %[uSrc], %[mask], %[uSrc], lsr #0x2" : [uSrc] "+r" (uSrc) : [mask] "r" (0x1ce7));
+  } else if (!SKIP_USRC_MSB_MASK) {
+    asm ("bic %[uSrc], %[uSrc], #0x8000" : [uSrc] "+r" (uSrc));
+  }
+
+  
+	// 0.5 x Back + 0.5 x Forward
+	if (BLENDMODE==0) {
+    // mix = ((uSrc + uDst) - ((uSrc ^ uDst) & 0x0421)) >> 1;
+    asm ("eor %[mix], %[uSrc], %[uDst]\n\t"
+         "and %[mix], %[mix], %[mask]\n\t"
+         "sub %[mix], %[uDst], %[mix]\n\t"
+         "add %[mix], %[uSrc], %[mix]\n\t"
+         "mov %[mix], %[mix], lsr #0x1\n\t"
+         : [mix] "=&r" (mix)
+         : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x0421));
+  }
+
+  if (BLENDMODE == 1 || BLENDMODE == 3) {
+    // u32 sum      = uSrc + uDst;
+		// u32 low_bits = (uSrc ^ uDst) & 0x0421;
+		// u32 carries  = (sum - low_bits) & 0x8420;
+		// u32 modulo   = sum - carries;
+		// u32 clamp    = carries - (carries >> 5);
+		// mix = modulo | clamp;
+
+    u32 sum;
+
+    asm ("add %[sum], %[uSrc], %[uDst]\n\t"
+         "eor %[mix], %[uSrc], %[uDst]\n\t"
+         "and %[mix], %[mix], %[mask]\n\t"
+         "sub %[mix], %[sum], %[mix]\n\t"
+         "and %[mix], %[mix], %[mask], lsl #0x05\n\t"
+         "sub %[sum], %[sum], %[mix] \n\t"
+         "sub %[mix], %[mix], %[mix], lsr #0x05\n\t"
+         "orr %[mix], %[sum], %[mix]"
+         : [sum] "=&r" (sum), [mix] "=&r" (mix)
+         : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x0421));
+  }
+    
+	// 1.0 x Back - 1.0 x Forward
+	if (BLENDMODE==2) {
+    u32 diff;
+    // u32 diff     = uDst - uSrc + 0x8420;
+		// u32 low_bits = (uDst ^ uSrc) & 0x8420;
+		// u32 borrows  = (diff - low_bits) & 0x8420;
+		// u32 modulo   = diff - borrows;
+		// u32 clamp    = borrows - (borrows >> 5);
+		// mix = modulo & clamp;
+    asm ("sub %[diff], %[uDst], %[uSrc]\n\t"
+         "add %[diff], %[diff], %[mask]\n\t"
+         "eor %[mix], %[uDst], %[uSrc]\n\t"
+         "and %[mix], %[mix], %[mask]\n\t"
+         "sub %[mix], %[diff], %[mix]\n\t"
+         "and %[mix], %[mix], %[mask]\n\t"
+         "sub %[diff], %[diff], %[mix]\n\t"
+         "sub %[mix], %[mix], %[mix], lsr #0x05\n\t"
+         "and %[mix], %[diff], %[mix]"
+         : [diff] "=&r" (diff), [mix] "=&r" (mix)
+         : [uSrc] "r" (uSrc), [uDst] "r" (uDst), [mask] "r" (0x8420));
+	}
+  
+	return mix;
+}
+
+#endif  //_OP_BLEND_ARM_H_