From 60143111ea9b7da7f9e78ee319fadea3b9d6f11d Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <pcc@google.com>
Date: Wed, 29 Aug 2018 16:13:01 -0700
Subject: [PATCH] libpixelflinger: Avoid using x18 register in blend
 implementation.

Instead, use x15 which is one of the available temporary registers.

Bug: 112907825
Test: test-pixelflinger-arm64-t32cb16blend
Change-Id: Icfcaae1d8163880eddc2862af92e5636a03d8b52
---
 libpixelflinger/arch-arm64/t32cb16blend.S | 26 +++++++++++------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/libpixelflinger/arch-arm64/t32cb16blend.S b/libpixelflinger/arch-arm64/t32cb16blend.S
index b1a950dbb..a9733c0e2 100644
--- a/libpixelflinger/arch-arm64/t32cb16blend.S
+++ b/libpixelflinger/arch-arm64/t32cb16blend.S
@@ -49,7 +49,7 @@
  *      upper 16-bit pixels in DREG into FB
  *
  *
- * clobbered: w6, w7, w16, w17, w18
+ * clobbered: w6, w7, w15, w16, w17
  *
  */
 
@@ -73,8 +73,8 @@
     add     w16, w6, w16, lsr #8
     cmp     w16, #0x1F
     orr     w17, \FB, #(0x1F<<(16 + 11))
-    orr     w18, \FB, w16, lsl #(16 + 11)
-    csel    \FB, w17, w18, hi
+    orr     w15, \FB, w16, lsl #(16 + 11)
+    csel    \FB, w17, w15, hi
         // green
         and     w6, \DREG, #(0x3F<<(16 + 5))
         lsr     w17,w6,#(16+5)
@@ -84,8 +84,8 @@
         add     w6, w16, w6, lsr #8
         cmp     w6, #0x3F
         orr     w17, \FB, #(0x3F<<(16 + 5))
-        orr     w18, \FB, w6, lsl #(16 + 5)
-        csel    \FB, w17, w18, hi
+        orr     w15, \FB, w6, lsl #(16 + 5)
+        csel    \FB, w17, w15, hi
             // blue
             and     w16, \DREG, #(0x1F << 16)
             lsr     w17,w16,#16
@@ -95,8 +95,8 @@
             add     w16, w6, w16, lsr #8
             cmp     w16, #0x1F
             orr     w17, \FB, #(0x1F << 16)
-            orr     w18, \FB, w16, lsl #16
-            csel    \FB, w17, w18, hi
+            orr     w15, \FB, w16, lsl #16
+            csel    \FB, w17, w15, hi
 
 .else //Blending even pixel present in bottom 16 bits of DREG register
 
@@ -109,8 +109,8 @@
     add     w16, w6, w16, lsr #8
     cmp     w16, #0x1F
     mov     w17, #(0x1F<<11)
-    lsl     w18, w16, #11
-    csel    \FB, w17, w18, hi
+    lsl     w15, w16, #11
+    csel    \FB, w17, w15, hi
 
 
         // green
@@ -121,8 +121,8 @@
         add     w6, w16, w6, lsr #(5+8)
         cmp     w6, #0x3F
         orr     w17, \FB, #(0x3F<<5)
-        orr     w18, \FB, w6, lsl #5
-        csel    \FB, w17, w18, hi
+        orr     w15, \FB, w6, lsl #5
+        csel    \FB, w17, w15, hi
 
             // blue
             and     w16, \DREG, #0x1F
@@ -132,8 +132,8 @@
             add     w16, w6, w16, lsr #8
             cmp     w16, #0x1F
             orr     w17, \FB, #0x1F
-            orr     w18, \FB, w16
-            csel    \FB, w17, w18, hi
+            orr     w15, \FB, w16
+            csel    \FB, w17, w15, hi
 
 .endif // End of blending even pixel