Merge tag 'android-11.0.0_r16' into android-10.0
Android 11.0.0 release 16 - twrp bringup patch
diff --git a/libpixelflinger/col32cb16blend.S b/libpixelflinger/col32cb16blend.S
new file mode 100644
index 0000000..39f94e1
--- /dev/null
+++ b/libpixelflinger/col32cb16blend.S
@@ -0,0 +1,77 @@
+/* libs/pixelflinger/col32cb16blend.S
+ *
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+ .text
+ .balign 4
+
+ .global scanline_col32cb16blend_arm
+
+//
+// This function alpha blends a fixed color into a destination scanline, using
+// the formula:
+//
+// d = s + (((a + (a >> 7)) * d) >> 8)
+//
+// where d is the destination pixel,
+// s is the source color,
+// a is the alpha channel of the source color.
+//
+
+// r0 = destination buffer pointer
+// r1 = color value
+// r2 = count
+
+
+scanline_col32cb16blend_arm:
+ push {r4-r10, lr} // stack ARM regs
+
+ mov r5, r1, lsr #24 // shift down alpha
+ mov r9, #0xff // create mask
+ add r5, r5, r5, lsr #7 // add in top bit
+ rsb r5, r5, #256 // invert alpha
+ and r10, r1, #0xff // extract red
+ and r12, r9, r1, lsr #8 // extract green
+ and r4, r9, r1, lsr #16 // extract blue
+ mov r10, r10, lsl #5 // prescale red
+ mov r12, r12, lsl #6 // prescale green
+ mov r4, r4, lsl #5 // prescale blue
+ mov r9, r9, lsr #2 // create dest green mask
+
+1:
+ ldrh r8, [r0] // load dest pixel
+ subs r2, r2, #1 // decrement loop counter
+ mov r6, r8, lsr #11 // extract dest red
+ and r7, r9, r8, lsr #5 // extract dest green
+ and r8, r8, #0x1f // extract dest blue
+
+ smlabb r6, r6, r5, r10 // dest red * alpha + src red
+ smlabb r7, r7, r5, r12 // dest green * alpha + src green
+ smlabb r8, r8, r5, r4 // dest blue * alpha + src blue
+
+ mov r6, r6, lsr #8 // shift down red
+ mov r7, r7, lsr #8 // shift down green
+ mov r6, r6, lsl #11 // shift red into 565
+ orr r6, r7, lsl #5 // shift green into 565
+ orr r6, r8, lsr #8 // shift blue into 565
+
+ strh r6, [r0], #2 // store pixel to dest, update ptr
+ bne 1b // if count != 0, loop
+
+ pop {r4-r10, pc} // return
+
+
+