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+/*
+ * Copyright (C) 2006 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.
+ */
+/*
+ * memset32.S
+ *
+ */
+
+ .text
+ .align
+
+ .global android_memset32
+ .type android_memset32, %function
+ .global android_memset16
+ .type android_memset16, %function
+
+ /*
+ * Optimized memset32 and memset16 for ARM.
+ *
+ * void android_memset16(uint16_t* dst, uint16_t value, size_t size);
+ * void android_memset32(uint32_t* dst, uint32_t value, size_t size);
+ *
+ */
+
+android_memset16:
+ .fnstart
+ cmp r2, #1
+ bxle lr
+
+ /* expand the data to 32 bits */
+ mov r1, r1, lsl #16
+ orr r1, r1, r1, lsr #16
+
+ /* align to 32 bits */
+ tst r0, #2
+ strneh r1, [r0], #2
+ subne r2, r2, #2
+ .fnend
+
+android_memset32:
+ .fnstart
+ .save {lr}
+ str lr, [sp, #-4]!
+
+ /* align the destination to a cache-line */
+ mov r12, r1
+ mov lr, r1
+ rsb r3, r0, #0
+ ands r3, r3, #0x1C
+ beq .Laligned32
+ cmp r3, r2
+ andhi r3, r2, #0x1C
+ sub r2, r2, r3
+
+ /* conditionally writes 0 to 7 words (length in r3) */
+ movs r3, r3, lsl #28
+ stmcsia r0!, {r1, lr}
+ stmcsia r0!, {r1, lr}
+ stmmiia r0!, {r1, lr}
+ movs r3, r3, lsl #2
+ strcs r1, [r0], #4
+
+.Laligned32:
+ mov r3, r1
+1: subs r2, r2, #32
+ stmhsia r0!, {r1,r3,r12,lr}
+ stmhsia r0!, {r1,r3,r12,lr}
+ bhs 1b
+ add r2, r2, #32
+
+ /* conditionally stores 0 to 30 bytes */
+ movs r2, r2, lsl #28
+ stmcsia r0!, {r1,r3,r12,lr}
+ stmmiia r0!, {r1,lr}
+ movs r2, r2, lsl #2
+ strcs r1, [r0], #4
+ strmih lr, [r0], #2
+
+ ldr lr, [sp], #4
+ bx lr
+ .fnend