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017f161a55
Enable the compiler intrinsic for byte swapping on arch ARM. This allows the compiler to detect and be able to optimize out byte swappings, and has a very modest benefit on vmlinux size (Linaro gcc 4.8): text data bss dec hex filename 2840310 123932 61960 3026202 2e2d1a vmlinux-lart #orig 2840152 123932 61960 3026044 2e2c7c vmlinux-lart #builtin-bswap 6473120 314840 5616016 12403976 bd4508 vmlinux-mxs #orig 6472586 314848 5616016 12403450 bd42fa vmlinux-mxs #builtin-bswap 7419872 318372 379556 8117800 7bde28 vmlinux-imx_v6_v7 #orig 7419170 318364 379556 8117090 7bdb62 vmlinux-imx_v6_v7 #builtin-bswap Signed-off-by: Kim Phillips <kim.phillips@freescale.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Acked-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
37 lines
591 B
ArmAsm
37 lines
591 B
ArmAsm
#include <linux/linkage.h>
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#if __LINUX_ARM_ARCH__ >= 6
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ENTRY(__bswapsi2)
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rev r0, r0
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bx lr
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ENDPROC(__bswapsi2)
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ENTRY(__bswapdi2)
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rev r3, r0
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rev r0, r1
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mov r1, r3
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bx lr
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ENDPROC(__bswapdi2)
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#else
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ENTRY(__bswapsi2)
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eor r3, r0, r0, ror #16
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mov r3, r3, lsr #8
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bic r3, r3, #0xff00
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eor r0, r3, r0, ror #8
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mov pc, lr
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ENDPROC(__bswapsi2)
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ENTRY(__bswapdi2)
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mov ip, r1
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eor r3, ip, ip, ror #16
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eor r1, r0, r0, ror #16
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mov r1, r1, lsr #8
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mov r3, r3, lsr #8
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bic r3, r3, #0xff00
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bic r1, r1, #0xff00
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eor r1, r1, r0, ror #8
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eor r0, r3, ip, ror #8
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mov pc, lr
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ENDPROC(__bswapdi2)
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#endif
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