ARM64: Move xSELF from x18 to x19.

This patch moves xSELF to callee saved x19 and removes support for
ETR (external thread register), previously used across native calls.

Change-Id: Icee07fbb9292425947f7de33d10a0ddf98c7899b
Signed-off-by: Serban Constantinescu <serban.constantinescu@linaro.org>
diff --git a/compiler/dex/quick/quick_cfi_test_expected.inc b/compiler/dex/quick/quick_cfi_test_expected.inc
index 48109d2..634fdee 100644
--- a/compiler/dex/quick/quick_cfi_test_expected.inc
+++ b/compiler/dex/quick/quick_cfi_test_expected.inc
@@ -33,15 +33,15 @@
 // 0x00000014: .cfi_def_cfa_offset: 64
 
 static constexpr uint8_t expected_asm_kArm64[] = {
-    0xFF, 0x03, 0x01, 0xD1, 0xE8, 0xA7, 0x01, 0x6D, 0xF3, 0xD3, 0x02, 0xA9,
+    0xFF, 0x03, 0x01, 0xD1, 0xE8, 0xA7, 0x01, 0x6D, 0xF4, 0xD7, 0x02, 0xA9,
     0xFE, 0x1F, 0x00, 0xF9, 0xE0, 0x03, 0x00, 0xB9, 0xE8, 0xA7, 0x41, 0x6D,
-    0xF3, 0xD3, 0x42, 0xA9, 0xFE, 0x1F, 0x40, 0xF9, 0xFF, 0x03, 0x01, 0x91,
+    0xF4, 0xD7, 0x42, 0xA9, 0xFE, 0x1F, 0x40, 0xF9, 0xFF, 0x03, 0x01, 0x91,
     0xC0, 0x03, 0x5F, 0xD6,
 };
 static constexpr uint8_t expected_cfi_kArm64[] = {
-    0x44, 0x0E, 0x40, 0x44, 0x05, 0x48, 0x0A, 0x05, 0x49, 0x08, 0x44, 0x93,
-    0x06, 0x94, 0x04, 0x44, 0x9E, 0x02, 0x44, 0x0A, 0x44, 0x06, 0x48, 0x06,
-    0x49, 0x44, 0xD3, 0xD4, 0x44, 0xDE, 0x44, 0x0E, 0x00, 0x44, 0x0B, 0x0E,
+    0x44, 0x0E, 0x40, 0x44, 0x05, 0x48, 0x0A, 0x05, 0x49, 0x08, 0x44, 0x94,
+    0x06, 0x95, 0x04, 0x44, 0x9E, 0x02, 0x44, 0x0A, 0x44, 0x06, 0x48, 0x06,
+    0x49, 0x44, 0xD4, 0xD5, 0x44, 0xDE, 0x44, 0x0E, 0x00, 0x44, 0x0B, 0x0E,
     0x40,
 };
 // 0x00000000: sub sp, sp, #0x40 (64)
@@ -49,9 +49,9 @@
 // 0x00000004: stp d8, d9, [sp, #24]
 // 0x00000008: .cfi_offset_extended: r72 at cfa-40
 // 0x00000008: .cfi_offset_extended: r73 at cfa-32
-// 0x00000008: stp x19, x20, [sp, #40]
-// 0x0000000c: .cfi_offset: r19 at cfa-24
-// 0x0000000c: .cfi_offset: r20 at cfa-16
+// 0x00000008: stp x20, x21, [sp, #40]
+// 0x0000000c: .cfi_offset: r20 at cfa-24
+// 0x0000000c: .cfi_offset: r21 at cfa-16
 // 0x0000000c: str lr, [sp, #56]
 // 0x00000010: .cfi_offset: r30 at cfa-8
 // 0x00000010: str w0, [sp]
@@ -59,9 +59,9 @@
 // 0x00000014: ldp d8, d9, [sp, #24]
 // 0x00000018: .cfi_restore_extended: r72
 // 0x00000018: .cfi_restore_extended: r73
-// 0x00000018: ldp x19, x20, [sp, #40]
-// 0x0000001c: .cfi_restore: r19
+// 0x00000018: ldp x20, x21, [sp, #40]
 // 0x0000001c: .cfi_restore: r20
+// 0x0000001c: .cfi_restore: r21
 // 0x0000001c: ldr lr, [sp, #56]
 // 0x00000020: .cfi_restore: r30
 // 0x00000020: add sp, sp, #0x40 (64)