From ec98f9a01ffb23ea72471ccbc8c390c8c2e4c0b3 Mon Sep 17 00:00:00 2001
From: "Maciej W. Rozycki" <macro@linux-mips.org>
Date: Fri, 3 Apr 2015 23:25:18 +0100
Subject: [PATCH] MIPS: math-emu: Update sNaN quieting handlers
Commit fdffbafb [Lots of FPU bug fixes from Kjeld Borch Egevang.]
replaced the two single `ieee754sp_nanxcpt' and `ieee754dp_nanxcpt'
places, where sNaN quieting used to happen for single and double
floating-point operations respectively, with individual qNaN
instantiations across all the call sites instead. It also made most of
these two functions dead code as where called on a qNaN they return
right away.
To revert the damage and make sNaN quieting uniform again first rewrite
`ieee754sp_nanxcpt' and `ieee754dp_nanxcpt' to do the same quieting all
the call sites do, that is return the default qNaN encoding for all
input sNaN values; never propagate any sNaN payload bits from its
trailing significand field.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9685/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
---
arch/mips/math-emu/ieee754dp.c | 11 +++--------
arch/mips/math-emu/ieee754sp.c | 11 +++--------
2 files changed, 6 insertions(+), 16 deletions(-)
diff --git a/arch/mips/math-emu/ieee754dp.c b/arch/mips/math-emu/ieee754dp.c
index 068f45a415fc..9723a518e5ad 100644
--- a/arch/mips/math-emu/ieee754dp.c
+++ b/arch/mips/math-emu/ieee754dp.c
@@ -49,14 +49,9 @@ union ieee754dp __cold ieee754dp_nanxcpt(union ieee754dp r)
if (!ieee754dp_issnan(r)) /* QNAN does not cause invalid op !! */
return r;
- if (!ieee754_setandtestcx(IEEE754_INVALID_OPERATION)) {
- /* not enabled convert to a quiet NaN */
- DPMANT(r) &= (~DP_MBIT(DP_FBITS-1));
- if (ieee754dp_isnan(r))
- return r;
- else
- return ieee754dp_indef();
- }
+ /* If not enabled convert to a quiet NaN. */
+ if (!ieee754_setandtestcx(IEEE754_INVALID_OPERATION))
+ return ieee754dp_indef();
return r;
}
diff --git a/arch/mips/math-emu/ieee754sp.c b/arch/mips/math-emu/ieee754sp.c
index ba88301579c2..7bde3c204d02 100644
--- a/arch/mips/math-emu/ieee754sp.c
+++ b/arch/mips/math-emu/ieee754sp.c
@@ -49,14 +49,9 @@ union ieee754sp __cold ieee754sp_nanxcpt(union ieee754sp r)
if (!ieee754sp_issnan(r)) /* QNAN does not cause invalid op !! */
return r;
- if (!ieee754_setandtestcx(IEEE754_INVALID_OPERATION)) {
- /* not enabled convert to a quiet NaN */
- SPMANT(r) &= (~SP_MBIT(SP_FBITS-1));
- if (ieee754sp_isnan(r))
- return r;
- else
- return ieee754sp_indef();
- }
+ /* If not enabled convert to a quiet NaN. */
+ if (!ieee754_setandtestcx(IEEE754_INVALID_OPERATION))
+ return ieee754sp_indef();
return r;
}
--
2.34.1