[PATCH 1/4] math-emu: Fix single float point division bug

Liu Yu yu.liu at freescale.com
Tue Oct 28 14:50:18 EST 2008


PowerPC float point division emulation is derived from gcc.
I reported this problem on gcc maillist and got this reply:
http://gcc.gnu.org/ml/gcc/2008-03/msg00543.html

Since UDIV_NEEDS_NORMALIZATION is not used by kernel, we should use
_FP_DIV_MEAT_1_udiv_norm to make sure the single float point
is normalized before udiv_qrnnd.

Signed-off-by: Liu Yu <yu.liu at freescale.com>
---
 arch/powerpc/include/asm/sfp-machine.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/include/asm/sfp-machine.h b/arch/powerpc/include/asm/sfp-machine.h
index ced34f1..da12ea7 100644
--- a/arch/powerpc/include/asm/sfp-machine.h
+++ b/arch/powerpc/include/asm/sfp-machine.h
@@ -82,7 +82,7 @@
 #define _FP_MUL_MEAT_S(R,X,Y)   _FP_MUL_MEAT_1_wide(_FP_WFRACBITS_S,R,X,Y,umul_ppmm)
 #define _FP_MUL_MEAT_D(R,X,Y)   _FP_MUL_MEAT_2_wide(_FP_WFRACBITS_D,R,X,Y,umul_ppmm)
 
-#define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_udiv(S,R,X,Y)
+#define _FP_DIV_MEAT_S(R,X,Y)	_FP_DIV_MEAT_1_udiv_norm(S,R,X,Y)
 #define _FP_DIV_MEAT_D(R,X,Y)	_FP_DIV_MEAT_2_udiv(D,R,X,Y)
 
 /* These macros define what NaN looks like. They're supposed to expand to
-- 
1.5.4




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