[PATCH 4.9 064/199] powerpc/math-emu: Update macros from GCC

From: Greg Kroah-Hartman
Date: Thu Dec 19 2019 - 14:06:42 EST


From: Joel Stanley <joel@xxxxxxxxx>

[ Upstream commit b682c8692442711684befe413cf93cf01c5324ea ]

The add_ssaaaa, sub_ddmmss, umul_ppmm and udiv_qrnnd macros originate
from GCC's longlong.h which in turn was copied from GMP's longlong.h a
few decades ago.

This was found when compiling with clang:

arch/powerpc/math-emu/fnmsub.c:46:2: error: invalid use of a cast in a
inline asm context requiring an l-value: remove the cast or build with
-fheinous-gnu-extensions
FP_ADD_D(R, T, B);
^~~~~~~~~~~~~~~~~
...

./arch/powerpc/include/asm/sfp-machine.h:283:27: note: expanded from
macro 'sub_ddmmss'
: "=r" ((USItype)(sh)), \
~~~~~~~~~~^~~

Segher points out: this was fixed in GCC over 16 years ago
( https://gcc.gnu.org/r56600 ), and in GMP (where it comes from)
presumably before that.

Update the add_ssaaaa, sub_ddmmss, umul_ppmm and udiv_qrnnd macros to
the latest GCC version in order to git rid of the invalid casts. These
were taken as-is from GCC's longlong in order to make future syncs
obvious. Other parts of sfp-machine.h were left as-is as the file
contains more features than present in longlong.h.

Link: https://github.com/ClangBuiltLinux/linux/issues/260
Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
Reviewed-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Reviewed-by: Segher Boessenkool <segher@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/powerpc/include/asm/sfp-machine.h | 92 ++++++++------------------
1 file changed, 29 insertions(+), 63 deletions(-)

diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
index d89beaba26ff9..8b957aabb826d 100644
--- a/arch/powerpc/include/asm/sfp-machine.h
+++ b/arch/powerpc/include/asm/sfp-machine.h
@@ -213,30 +213,18 @@
* respectively. The result is placed in HIGH_SUM and LOW_SUM. Overflow
* (i.e. carry out) is not stored anywhere, and is lost.
*/
-#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
+#define add_ssaaaa(sh, sl, ah, al, bh, bl) \
do { \
if (__builtin_constant_p (bh) && (bh) == 0) \
- __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{aze|addze} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "%r" ((USItype)(ah)), \
- "%r" ((USItype)(al)), \
- "rI" ((USItype)(bl))); \
- else if (__builtin_constant_p (bh) && (bh) ==~(USItype) 0) \
- __asm__ ("{a%I4|add%I4c} %1,%3,%4\n\t{ame|addme} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "%r" ((USItype)(ah)), \
- "%r" ((USItype)(al)), \
- "rI" ((USItype)(bl))); \
+ __asm__ ("add%I4c %1,%3,%4\n\taddze %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (ah), "%r" (al), "rI" (bl));\
+ else if (__builtin_constant_p (bh) && (bh) == ~(USItype) 0) \
+ __asm__ ("add%I4c %1,%3,%4\n\taddme %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (ah), "%r" (al), "rI" (bl));\
else \
- __asm__ ("{a%I5|add%I5c} %1,%4,%5\n\t{ae|adde} %0,%2,%3" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "%r" ((USItype)(ah)), \
- "r" ((USItype)(bh)), \
- "%r" ((USItype)(al)), \
- "rI" ((USItype)(bl))); \
+ __asm__ ("add%I5c %1,%4,%5\n\tadde %0,%2,%3" \
+ : "=r" (sh), "=&r" (sl) \
+ : "%r" (ah), "r" (bh), "%r" (al), "rI" (bl)); \
} while (0)

/* sub_ddmmss is used in op-2.h and udivmodti4.c and should be equivalent to
@@ -248,44 +236,24 @@
* and LOW_DIFFERENCE. Overflow (i.e. carry out) is not stored anywhere,
* and is lost.
*/
-#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
+#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
do { \
if (__builtin_constant_p (ah) && (ah) == 0) \
- __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfze|subfze} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "r" ((USItype)(bh)), \
- "rI" ((USItype)(al)), \
- "r" ((USItype)(bl))); \
- else if (__builtin_constant_p (ah) && (ah) ==~(USItype) 0) \
- __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{sfme|subfme} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "r" ((USItype)(bh)), \
- "rI" ((USItype)(al)), \
- "r" ((USItype)(bl))); \
+ __asm__ ("subf%I3c %1,%4,%3\n\tsubfze %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (bh), "rI" (al), "r" (bl));\
+ else if (__builtin_constant_p (ah) && (ah) == ~(USItype) 0) \
+ __asm__ ("subf%I3c %1,%4,%3\n\tsubfme %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (bh), "rI" (al), "r" (bl));\
else if (__builtin_constant_p (bh) && (bh) == 0) \
- __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{ame|addme} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "r" ((USItype)(ah)), \
- "rI" ((USItype)(al)), \
- "r" ((USItype)(bl))); \
- else if (__builtin_constant_p (bh) && (bh) ==~(USItype) 0) \
- __asm__ ("{sf%I3|subf%I3c} %1,%4,%3\n\t{aze|addze} %0,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "r" ((USItype)(ah)), \
- "rI" ((USItype)(al)), \
- "r" ((USItype)(bl))); \
+ __asm__ ("subf%I3c %1,%4,%3\n\taddme %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (ah), "rI" (al), "r" (bl));\
+ else if (__builtin_constant_p (bh) && (bh) == ~(USItype) 0) \
+ __asm__ ("subf%I3c %1,%4,%3\n\taddze %0,%2" \
+ : "=r" (sh), "=&r" (sl) : "r" (ah), "rI" (al), "r" (bl));\
else \
- __asm__ ("{sf%I4|subf%I4c} %1,%5,%4\n\t{sfe|subfe} %0,%3,%2" \
- : "=r" ((USItype)(sh)), \
- "=&r" ((USItype)(sl)) \
- : "r" ((USItype)(ah)), \
- "r" ((USItype)(bh)), \
- "rI" ((USItype)(al)), \
- "r" ((USItype)(bl))); \
+ __asm__ ("subf%I4c %1,%5,%4\n\tsubfe %0,%3,%2" \
+ : "=r" (sh), "=&r" (sl) \
+ : "r" (ah), "r" (bh), "rI" (al), "r" (bl)); \
} while (0)

/* asm fragments for mul and div */
@@ -294,13 +262,10 @@
* UWtype integers MULTIPLER and MULTIPLICAND, and generates a two UWtype
* word product in HIGH_PROD and LOW_PROD.
*/
-#define umul_ppmm(ph, pl, m0, m1) \
+#define umul_ppmm(ph, pl, m0, m1) \
do { \
USItype __m0 = (m0), __m1 = (m1); \
- __asm__ ("mulhwu %0,%1,%2" \
- : "=r" ((USItype)(ph)) \
- : "%r" (__m0), \
- "r" (__m1)); \
+ __asm__ ("mulhwu %0,%1,%2" : "=r" (ph) : "%r" (m0), "r" (m1)); \
(pl) = __m0 * __m1; \
} while (0)

@@ -312,9 +277,10 @@
* significant bit of DENOMINATOR must be 1, then the pre-processor symbol
* UDIV_NEEDS_NORMALIZATION is defined to 1.
*/
-#define udiv_qrnnd(q, r, n1, n0, d) \
+#define udiv_qrnnd(q, r, n1, n0, d) \
do { \
- UWtype __d1, __d0, __q1, __q0, __r1, __r0, __m; \
+ UWtype __d1, __d0, __q1, __q0; \
+ UWtype __r1, __r0, __m; \
__d1 = __ll_highpart (d); \
__d0 = __ll_lowpart (d); \
\
@@ -325,7 +291,7 @@
if (__r1 < __m) \
{ \
__q1--, __r1 += (d); \
- if (__r1 >= (d)) /* we didn't get carry when adding to __r1 */ \
+ if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
if (__r1 < __m) \
__q1--, __r1 += (d); \
} \
--
2.20.1