linux-kernel - [PATCH v2 3/3] asm-generic: div64: Remove always-true __div64_const32_is

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Date:   Wed, 14 Jul 2021 12:04:10 +0200
From:   Geert Uytterhoeven <geert+renesas@...der.be>
To:     Russell King <linux@...linux.org.uk>, Arnd Bergmann <arnd@...db.de>
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Geert Uytterhoeven <geert+renesas@...der.be>
Subject: [PATCH v2 3/3] asm-generic: div64: Remove always-true __div64_const32_is_OK()

Since commit cafa0010cd51fb71 ("Raise the minimum required gcc version
to 4.6"), the kernel can no longer be compiled using gcc-3.
Hence __div64_const32_is_OK() is always true, and the corresponding
check can thus be removed.

While at it, remove the whitespace error that hurts my eyes, and add the
missing curly braces for the final else statement, as per coding style.

Signed-off-by: Geert Uytterhoeven <geert+renesas@...der.be>
Acked-by: Arnd Bergmann <arnd@...db.de>
---
v2:
  - Add Acked-by.
---
 include/asm-generic/div64.h | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/include/asm-generic/div64.h b/include/asm-generic/div64.h
index cd905b44a6300bf7..13f5aa68a4552a09 100644
--- a/include/asm-generic/div64.h
+++ b/include/asm-generic/div64.h
@@ -57,17 +57,11 @@
 /*
  * If the divisor happens to be constant, we determine the appropriate
  * inverse at compile time to turn the division into a few inline
- * multiplications which ought to be much faster. And yet only if compiling
- * with a sufficiently recent gcc version to perform proper 64-bit constant
- * propagation.
+ * multiplications which ought to be much faster.
  *
  * (It is unfortunate that gcc doesn't perform all this internally.)
  */
 
-#ifndef __div64_const32_is_OK
-#define __div64_const32_is_OK (__GNUC__ >= 4)
-#endif
-
 #define __div64_const32(n, ___b)					\
 ({									\
 	/*								\
@@ -230,8 +224,7 @@ extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
 	    is_power_of_2(__base)) {			\
 		__rem = (n) & (__base - 1);		\
 		(n) >>= ilog2(__base);			\
-	} else if (__div64_const32_is_OK &&		\
-		   __builtin_constant_p(__base) &&	\
+	} else if (__builtin_constant_p(__base) &&	\
 		   __base != 0) {			\
 		uint32_t __res_lo, __n_lo = (n);	\
 		(n) = __div64_const32(n, __base);	\
@@ -241,8 +234,9 @@ extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
 	} else if (likely(((n) >> 32) == 0)) {		\
 		__rem = (uint32_t)(n) % __base;		\
 		(n) = (uint32_t)(n) / __base;		\
-	} else 						\
+	} else {					\
 		__rem = __div64_32(&(n), __base);	\
+	}						\
 	__rem;						\
  })
 
-- 
2.25.1