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-rw-r--r--sysdeps/arm/armv7/strcmp.S118
1 files changed, 32 insertions, 86 deletions
diff --git a/sysdeps/arm/armv7/strcmp.S b/sysdeps/arm/armv7/strcmp.S
index 5bcaf21ee2..2626fdf72e 100644
--- a/sysdeps/arm/armv7/strcmp.S
+++ b/sysdeps/arm/armv7/strcmp.S
@@ -1,5 +1,5 @@
/* strcmp implementation for ARMv7-A, optimized for Cortex-A15.
- Copyright (C) 2012-2016 Free Software Foundation, Inc.
+ Copyright (C) 2012-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
@@ -83,8 +83,6 @@
#define syndrome tmp2
-#ifndef NO_THUMB
-/* This code is best on Thumb. */
.thumb
/* In Thumb code we can't use MVN with a register shift, but we do have ORN. */
@@ -94,27 +92,6 @@
.macro apply_mask data_reg, mask_reg
orn \data_reg, \data_reg, \mask_reg
.endm
-#else
-/* In ARM code we don't have ORN, but we can use MVN with a register shift. */
-.macro prepare_mask mask_reg, nbits_reg
- mvn \mask_reg, const_m1, S2HI \nbits_reg
-.endm
-.macro apply_mask data_reg, mask_reg
- orr \data_reg, \data_reg, \mask_reg
-.endm
-
-/* These clobber the condition codes, which the real Thumb cbz/cbnz
- instructions do not. But it doesn't matter for any of the uses here. */
-.macro cbz reg, label
- cmp \reg, #0
- beq \label
-.endm
-.macro cbnz reg, label
- cmp \reg, #0
- bne \label
-.endm
-#endif
-
/* Macro to compute and return the result value for word-aligned
cases. */
@@ -178,10 +155,8 @@
#endif
ENTRY (strcmp)
#if STRCMP_PRECHECK == 1
- sfi_breg src1, \
- ldrb r2, [\B]
- sfi_breg src2, \
- ldrb r3, [\B]
+ ldrb r2, [src1]
+ ldrb r3, [src2]
cmp r2, #1
it cs
cmpcs r2, r3
@@ -211,11 +186,9 @@ ENTRY (strcmp)
and tmp2, tmp1, #3
bic src2, src2, #7
lsl tmp2, tmp2, #3 /* Bytes -> bits. */
- sfi_breg src1, \
- ldrd data1a, data1b, [\B], #16
+ ldrd data1a, data1b, [src1], #16
tst tmp1, #4
- sfi_breg src2, \
- ldrd data2a, data2b, [\B], #16
+ ldrd data2a, data2b, [src2], #16
prepare_mask tmp1, tmp2
apply_mask data1a, tmp1
apply_mask data2a, tmp1
@@ -231,10 +204,8 @@ ENTRY (strcmp)
.p2align 5,,12 /* Don't start in the tail bytes of a cache line. */
.p2align 2 /* Always word aligned. */
.Lloop_aligned8:
- sfi_breg src1, \
- ldrd data1a, data1b, [\B], #16
- sfi_breg src2, \
- ldrd data2a, data2b, [\B], #16
+ ldrd data1a, data1b, [src1], #16
+ ldrd data2a, data2b, [src2], #16
.Lstart_realigned8:
uadd8 syndrome_b, data1a, const_m1 /* Only want GE bits, */
eor syndrome_a, data1a, data2a
@@ -245,10 +216,8 @@ ENTRY (strcmp)
sel syndrome_b, syndrome_b, const_m1
cbnz syndrome_b, .Ldiff_in_b
- sfi_breg src1, \
- ldrd data1a, data1b, [\B, #-8]
- sfi_breg src2, \
- ldrd data2a, data2b, [\B, #-8]
+ ldrd data1a, data1b, [src1, #-8]
+ ldrd data2a, data2b, [src2, #-8]
uadd8 syndrome_b, data1a, const_m1 /* Only want GE bits, */
eor syndrome_a, data1a, data2a
sel syndrome_a, syndrome_a, const_m1
@@ -279,19 +248,15 @@ ENTRY (strcmp)
/* Unrolled by a factor of 2, to reduce the number of post-increment
operations. */
.Lloop_aligned4:
- sfi_breg src1, \
- ldr data1, [\B], #8
- sfi_breg src2, \
- ldr data2, [\B], #8
+ ldr data1, [src1], #8
+ ldr data2, [src2], #8
.Lstart_realigned4:
uadd8 syndrome, data1, const_m1 /* Only need GE bits. */
eor syndrome, data1, data2
sel syndrome, syndrome, const_m1
cbnz syndrome, .Laligned4_done
- sfi_breg src1, \
- ldr data1, [\B, #-4]
- sfi_breg src2, \
- ldr data2, [\B, #-4]
+ ldr data1, [src1, #-4]
+ ldr data2, [src2, #-4]
uadd8 syndrome, data1, const_m1
eor syndrome, data1, data2
sel syndrome, syndrome, const_m1
@@ -307,11 +272,9 @@ ENTRY (strcmp)
masking off the unwanted loaded data to prevent a difference. */
lsl tmp1, tmp1, #3 /* Bytes -> bits. */
bic src1, src1, #3
- sfi_breg src1, \
- ldr data1, [\B], #8
+ ldr data1, [src1], #8
bic src2, src2, #3
- sfi_breg src2, \
- ldr data2, [\B], #8
+ ldr data2, [src2], #8
prepare_mask tmp1, tmp1
apply_mask data1, tmp1
@@ -324,30 +287,26 @@ ENTRY (strcmp)
sub src2, src2, tmp1
bic src1, src1, #3
lsls tmp1, tmp1, #31
- sfi_breg src1, \
- ldr data1, [\B], #4
+ ldr data1, [src1], #4
beq .Laligned_m2
bcs .Laligned_m1
#if STRCMP_PRECHECK == 0
- sfi_breg src2, \
- ldrb data2, [\B, #1]
+ ldrb data2, [src2, #1]
uxtb tmp1, data1, ror #BYTE1_OFFSET
subs tmp1, tmp1, data2
bne .Lmisaligned_exit
cbz data2, .Lmisaligned_exit
.Laligned_m2:
- sfi_breg src2, \
- ldrb data2, [\B, #2]
+ ldrb data2, [src2, #2]
uxtb tmp1, data1, ror #BYTE2_OFFSET
subs tmp1, tmp1, data2
bne .Lmisaligned_exit
cbz data2, .Lmisaligned_exit
.Laligned_m1:
- sfi_breg src2, \
- ldrb data2, [\B, #3]
+ ldrb data2, [src2, #3]
uxtb tmp1, data1, ror #BYTE3_OFFSET
subs tmp1, tmp1, data2
bne .Lmisaligned_exit
@@ -356,16 +315,14 @@ ENTRY (strcmp)
#else /* STRCMP_PRECHECK */
/* If we've done the pre-check, then we don't need to check the
first byte again here. */
- sfi_breg src2, \
- ldrb data2, [\B, #2]
+ ldrb data2, [src2, #2]
uxtb tmp1, data1, ror #BYTE2_OFFSET
subs tmp1, tmp1, data2
bne .Lmisaligned_exit
cbz data2, .Lmisaligned_exit
.Laligned_m2:
- sfi_breg src2, \
- ldrb data2, [\B, #3]
+ ldrb data2, [src2, #3]
uxtb tmp1, data1, ror #BYTE3_OFFSET
subs tmp1, tmp1, data2
bne .Lmisaligned_exit
@@ -391,13 +348,11 @@ ENTRY (strcmp)
cfi_restore_state
/* src1 is word aligned, but src2 has no common alignment
with it. */
- sfi_breg src1, \
- ldr data1, [\B], #4
+ ldr data1, [src1], #4
lsls tmp1, src2, #31 /* C=src2[1], Z=src2[0]. */
bic src2, src2, #3
- sfi_breg src2, \
- ldr data2, [\B], #4
+ ldr data2, [src2], #4
bhi .Loverlap1 /* C=1, Z=0 => src2[1:0] = 0b11. */
bcs .Loverlap2 /* C=1, Z=1 => src2[1:0] = 0b10. */
@@ -409,13 +364,11 @@ ENTRY (strcmp)
sel syndrome, syndrome, const_m1
bne 4f
cbnz syndrome, 5f
- sfi_breg src2, \
- ldr data2, [\B], #4
+ ldr data2, [src2], #4
eor tmp1, tmp1, data1
cmp tmp1, data2, S2HI #24
bne 6f
- sfi_breg src1, \
- ldr data1, [\B], #4
+ ldr data1, [src1], #4
b .Loverlap3
4:
S2LO data2, data2, #8
@@ -427,8 +380,7 @@ ENTRY (strcmp)
/* We can only get here if the MSB of data1 contains 0, so
fast-path the exit. */
- sfi_breg src2, \
- ldrb result, [\B]
+ ldrb result, [src2]
ldrd r4, r5, [sp], #16
cfi_remember_state
cfi_def_cfa_offset (0)
@@ -454,13 +406,11 @@ ENTRY (strcmp)
sel syndrome, syndrome, const_m1
bne 4f
cbnz syndrome, 5f
- sfi_breg src2, \
- ldr data2, [\B], #4
+ ldr data2, [src2], #4
eor tmp1, tmp1, data1
cmp tmp1, data2, S2HI #16
bne 6f
- sfi_breg src1, \
- ldr data1, [\B], #4
+ ldr data1, [src1], #4
b .Loverlap2
4:
S2LO data2, data2, #16
@@ -469,8 +419,7 @@ ENTRY (strcmp)
ands syndrome, syndrome, const_m1, S2LO #16
bne .Lstrcmp_done_equal
- sfi_breg src2, \
- ldrh data2, [\B]
+ ldrh data2, [src2]
S2LO data1, data1, #16
#ifdef __ARM_BIG_ENDIAN
lsl data2, data2, #16
@@ -490,13 +439,11 @@ ENTRY (strcmp)
sel syndrome, syndrome, const_m1
bne 4f
cbnz syndrome, 5f
- sfi_breg src2, \
- ldr data2, [\B], #4
+ ldr data2, [src2], #4
eor tmp1, tmp1, data1
cmp tmp1, data2, S2HI #8
bne 6f
- sfi_breg src1, \
- ldr data1, [\B], #4
+ ldr data1, [src1], #4
b .Loverlap1
4:
S2LO data2, data2, #24
@@ -504,8 +451,7 @@ ENTRY (strcmp)
5:
tst syndrome, #LSB
bne .Lstrcmp_done_equal
- sfi_breg src2, \
- ldr data2, [\B]
+ ldr data2, [src2]
6:
S2LO data1, data1, #8
bic data2, data2, #MSB
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-30 08:09:54 +0000