From: Arnd Bergmann arnd@arndb.de
[ Upstream commit 29e7e9664aec17b94a9c8c5a75f8d216a206aa3a ]
clang warns about a few parts of the math-emu implementation where a 16-bit integer becomes negative during assignment:
arch/x86/math-emu/poly_tan.c:88:35: error: implicit conversion from 'int' to 'short' changes value from 49216 to -16320 [-Werror,-Wconstant-conversion] (0x41 + EXTENDED_Ebias) | SIGN_Negative); ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~ arch/x86/math-emu/fpu_emu.h:180:58: note: expanded from macro 'setexponent16' #define setexponent16(x,y) { (*(short *)&((x)->exp)) = (y); } ~ ^ arch/x86/math-emu/reg_constant.c:37:32: error: implicit conversion from 'int' to 'short' changes value from 49085 to -16451 [-Werror,-Wconstant-conversion] FPU_REG const CONST_PI2extra = MAKE_REG(NEG, -66, ^~~~~~~~~~~~~~~~~~ arch/x86/math-emu/reg_constant.c:21:25: note: expanded from macro 'MAKE_REG' ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) } ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/math-emu/reg_constant.c:48:28: error: implicit conversion from 'int' to 'short' changes value from 65535 to -1 [-Werror,-Wconstant-conversion] FPU_REG const CONST_QNaN = MAKE_REG(NEG, EXP_OVER, 0x00000000, 0xC0000000); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/x86/math-emu/reg_constant.c:21:25: note: expanded from macro 'MAKE_REG' ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) } ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~
The code is correct as is, so add a typecast to shut up the warnings.
Signed-off-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lkml.kernel.org/r/20190712090816.350668-1-arnd@arndb.de Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/math-emu/fpu_emu.h | 2 +- arch/x86/math-emu/reg_constant.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/math-emu/fpu_emu.h b/arch/x86/math-emu/fpu_emu.h index afbc4d805d66..df5aee5402c4 100644 --- a/arch/x86/math-emu/fpu_emu.h +++ b/arch/x86/math-emu/fpu_emu.h @@ -176,7 +176,7 @@ static inline void reg_copy(FPU_REG const *x, FPU_REG *y) #define setexponentpos(x,y) { (*(short *)&((x)->exp)) = \ ((y) + EXTENDED_Ebias) & 0x7fff; } #define exponent16(x) (*(short *)&((x)->exp)) -#define setexponent16(x,y) { (*(short *)&((x)->exp)) = (y); } +#define setexponent16(x,y) { (*(short *)&((x)->exp)) = (u16)(y); } #define addexponent(x,y) { (*(short *)&((x)->exp)) += (y); } #define stdexp(x) { (*(short *)&((x)->exp)) += EXTENDED_Ebias; }
diff --git a/arch/x86/math-emu/reg_constant.c b/arch/x86/math-emu/reg_constant.c index 00548354912f..382093c5072b 100644 --- a/arch/x86/math-emu/reg_constant.c +++ b/arch/x86/math-emu/reg_constant.c @@ -17,7 +17,7 @@ #include "control_w.h"
#define MAKE_REG(s, e, l, h) { l, h, \ - ((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) } + (u16)((EXTENDED_Ebias+(e)) | ((SIGN_##s != 0)*0x8000)) }
FPU_REG const CONST_1 = MAKE_REG(POS, 0, 0x00000000, 0x80000000); #if 0