diff options
Diffstat (limited to 'MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S')
-rw-r--r-- | MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S b/MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S new file mode 100644 index 0000000000..c1755539d3 --- /dev/null +++ b/MdePkg/Library/BaseMemoryLibOptDxe/Arm/SetMem.S @@ -0,0 +1,77 @@ +#------------------------------------------------------------------------------
+#
+# Copyright (c) 2016, Linaro Ltd. All rights reserved.<BR>
+#
+# This program and the accompanying materials are licensed and made available
+# under the terms and conditions of the BSD License which accompanies this
+# distribution. The full text of the license may be found at
+# http://opensource.org/licenses/bsd-license.php
+#
+# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+#
+#------------------------------------------------------------------------------
+
+ .text
+ .thumb
+ .syntax unified
+ .align 5
+ASM_GLOBAL ASM_PFX(InternalMemZeroMem)
+ASM_PFX(InternalMemZeroMem):
+ movs r2, #0
+
+ASM_GLOBAL ASM_PFX(InternalMemSetMem)
+ASM_PFX(InternalMemSetMem):
+ uxtb r2, r2
+ orr r2, r2, r2, lsl #8
+
+ASM_GLOBAL ASM_PFX(InternalMemSetMem16)
+ASM_PFX(InternalMemSetMem16):
+ uxth r2, r2
+ orr r2, r2, r2, lsl #16
+
+ASM_GLOBAL ASM_PFX(InternalMemSetMem32)
+ASM_PFX(InternalMemSetMem32):
+ mov r3, r2
+
+ASM_GLOBAL ASM_PFX(InternalMemSetMem64)
+ASM_PFX(InternalMemSetMem64):
+ push {r4, lr}
+ cmp r1, #16 // fewer than 16 bytes of input?
+ add r1, r1, r0 // r1 := dst + length
+ add lr, r0, #16
+ blt 2f
+ bic lr, lr, #15 // align output pointer
+
+ str r2, [r0] // potentially unaligned store of 4 bytes
+ str r3, [r0, #4] // potentially unaligned store of 4 bytes
+ str r2, [r0, #8] // potentially unaligned store of 4 bytes
+ str r3, [r0, #12] // potentially unaligned store of 4 bytes
+ beq 1f
+
+0: add lr, lr, #16 // advance the output pointer by 16 bytes
+ subs r4, r1, lr // past the output?
+ blt 3f // break out of the loop
+ strd r2, r3, [lr, #-16] // aligned store of 16 bytes
+ strd r2, r3, [lr, #-8]
+ bne 0b // goto beginning of loop
+1: pop {r4, pc}
+
+2: subs r4, r1, lr
+3: adds r4, r4, #16
+ subs r1, r1, #8
+ cmp r4, #4 // between 4 and 15 bytes?
+ blt 4f
+ cmp r4, #8 // between 8 and 15 bytes?
+ str r2, [lr, #-16] // overlapping store of 4 + (4 + 4) + 4 bytes
+ itt gt
+ strgt r3, [lr, #-12]
+ strgt r2, [r1]
+ str r3, [r1, #4]
+ pop {r4, pc}
+
+4: cmp r4, #2 // 2 or 3 bytes?
+ strb r2, [lr, #-16] // store 1 byte
+ it ge
+ strhge r2, [r1, #6] // store 2 bytes
+ pop {r4, pc}
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