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minmax: reduce min/max macro expansion in atomisp driver

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Avoid unnecessary nested min()/max() which results in egregious macro
expansion.

Use clamp_t() as this introduces the least possible expansion, and turn
the {s,u}DIGIT_FITTING() macros into inline functions to avoid the
nested expansion.

This resolves an issue with slackware 15.0 32-bit compilation as
reported by Richard Narron.

Presumably the min/max fixups would be difficult to backport, this patch
should be easier and fix's Richard's problem in 5.15.

Reported-by: Richard Narron <richard@aaazen.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Closes: https://lore.kernel.org/all/4a5321bd-b1f-1832-f0c-cea8694dc5aa@aaazen.com/
Fixes: 867046cc70 ("minmax: relax check to allow comparison between unsigned arguments and signed constants")
Cc: stable@vger.kernel.org
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Lorenzo Stoakes 2024-09-11 18:51:11 +01:00 committed by Linus Torvalds
parent 8d8d276ba2
commit 7c6a3a65ac
1 changed files with 19 additions and 7 deletions
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26
drivers/staging/media/atomisp/pci/sh_css_frac.h
View File

@ -32,12 +32,24 @@
#define uISP_VAL_MAX ((unsigned int)((1 << uISP_REG_BIT) - 1))
/* a:fraction bits for 16bit precision, b:fraction bits for ISP precision */
#define sDIGIT_FITTING(v, a, b) \
min_t(int, max_t(int, (((v) >> sSHIFT) >> max(sFRACTION_BITS_FITTING(a) - (b), 0)), \
sISP_VAL_MIN), sISP_VAL_MAX)
#define uDIGIT_FITTING(v, a, b) \
min((unsigned int)max((unsigned)(((v) >> uSHIFT) \
>> max((int)(uFRACTION_BITS_FITTING(a) - (b)), 0)), \
uISP_VAL_MIN), uISP_VAL_MAX)
static inline int sDIGIT_FITTING(int v, int a, int b)
{
int fit_shift = sFRACTION_BITS_FITTING(a) - b;
v >>= sSHIFT;
v >>= fit_shift > 0 ? fit_shift : 0;
return clamp_t(int, v, sISP_VAL_MIN, sISP_VAL_MAX);
}
static inline unsigned int uDIGIT_FITTING(unsigned int v, int a, int b)
{
int fit_shift = uFRACTION_BITS_FITTING(a) - b;
v >>= uSHIFT;
v >>= fit_shift > 0 ? fit_shift : 0;
return clamp_t(unsigned int, v, uISP_VAL_MIN, uISP_VAL_MAX);
}
#endif /* __SH_CSS_FRAC_H */