Patch "MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of both infinite inputs" has been added to the 4.9-stable tree

PATCH [email protected] 1 participant 1 message Sep 21, 2017

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2017-09-21 13:54 UTC #0 lore raw

This is a note to let you know that I've just added the patch titled

MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of both infinite inputs

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
mips-math-emu-maxa-mina-.-d-s-fix-cases-of-both-infinite-inputs.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 3444c4eb534c20e44f0d6670b34263efaf8b531f Mon Sep 17 00:00:00 2001

From: Aleksandar Markovic <[email protected]>
Date: Thu, 27 Jul 2017 18:08:52 +0200
Subject: MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of both infinite inputs

From: Aleksandar Markovic <[email protected]>

commit 3444c4eb534c20e44f0d6670b34263efaf8b531f upstream.

Fix the value returned by <MAXA|MINA>.<D|S> fd,fs,ft, if both inputs are infinite. The previous implementation returned always the value contained in ft in such cases. The correct behavior is specified in Mips instruction set manual and is as follows:

fs ft MAXA MINA
---------------------------------

    inf   inf        inf      inf
    inf  -inf        inf     -inf
   -inf   inf        inf     -inf

-inf -inf -inf -inf

A relevant example:

MAXA.S fd,fs,ft:
If fs contains +inf, and ft contains -inf, fd is going to contain +inf (without this patch, it used to contain -inf).

Fixes a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")

Fixes 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by Miodrag Dinic <[email protected]>

Signed-off-by Goran Ferenc <[email protected]>

Signed-off-by Aleksandar Markovic <[email protected]>

Reviewed-by James Hogan <[email protected]>

Cc Bo Hu <[email protected]>

Cc Douglas Leung <[email protected]>

Cc Jin Qian <[email protected]>

Cc Paul Burton <[email protected]>

Cc Petar Jovanovic <[email protected]>

Cc Raghu Gandham <[email protected]>

Cc [email protected]

Patchwork: https://patchwork.linux-mips.org/patch/16884/

Signed-off-by Ralf Baechle <[email protected]>

Signed-off-by Greg Kroah-Hartman <[email protected]>

---
 arch/mips/math-emu/dp_fmax.c |    4 +++-
 arch/mips/math-emu/dp_fmin.c |    4 +++-
 arch/mips/math-emu/sp_fmax.c |    4 +++-
 arch/mips/math-emu/sp_fmin.c |    4 +++-
 4 files changed, 12 insertions(+), 4 deletions(-)

arch/mips/math-emu/dp_fmax.c +3 -1

@@ -202,6 +202,9 @@ union ieee754dp ieee754dp_fmaxa(union ie
 	/*
 	 * Infinity and zero handling
 	 */
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+		return ieee754dp_inf(xs & ys);
+
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):

@@ -209,7 +212,6 @@ union ieee754dp ieee754dp_fmaxa(union ie
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
 		return x;
 
-	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):

arch/mips/math-emu/dp_fmin.c +3 -1

@@ -202,6 +202,9 @@ union ieee754dp ieee754dp_fmina(union ie
 	/*
 	 * Infinity and zero handling
 	 */
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+		return ieee754dp_inf(xs | ys);
+
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):

@@ -209,7 +212,6 @@ union ieee754dp ieee754dp_fmina(union ie
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
 		return x;
 
-	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):

arch/mips/math-emu/sp_fmax.c +3 -1

@@ -202,6 +202,9 @@ union ieee754sp ieee754sp_fmaxa(union ie
 	/*
 	 * Infinity and zero handling
 	 */
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+		return ieee754sp_inf(xs & ys);
+
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):

@@ -209,7 +212,6 @@ union ieee754sp ieee754sp_fmaxa(union ie
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
 		return x;
 
-	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):

arch/mips/math-emu/sp_fmin.c +3 -1

@@ -202,6 +202,9 @@ union ieee754sp ieee754sp_fmina(union ie
 	/*
 	 * Infinity and zero handling
 	 */
+	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
+		return ieee754sp_inf(xs | ys);
+
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM):
 	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM):

@@ -209,7 +212,6 @@ union ieee754sp ieee754sp_fmina(union ie
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO):
 		return x;
 
-	case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF):
 	case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF):

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/mips-math-emu-maddf-msubf-.-d-s-fix-nan-propagation.patch queue-4.9/mips-math-emu-max-maxa-min-mina-.-d-s-fix-cases-of-both-inputs-zero.patch queue-4.9/mips-math-emu-handle-zero-accumulator-case-in-maddf-and-msubf-separately.patch queue-4.9/mips-math-emu-max-min-.-d-s-fix-cases-of-both-inputs-negative.patch queue-4.9/mips-math-emu-max-maxa-min-mina-.-d-s-fix-quiet-nan-propagation.patch queue-4.9/mips-math-emu-maddf-msubf-.d-fix-accuracy-64-bit-case.patch queue-4.9/mips-math-emu-maddf-msubf-.s-fix-accuracy-32-bit-case.patch queue-4.9/mips-math-emu-maxa-mina-.-d-s-fix-cases-of-input-values-with-opposite-signs.patch queue-4.9/mips-math-emu-maxa-mina-.-d-s-fix-cases-of-both-infinite-inputs.patch queue-4.9/mips-math-emu-mina.-d-s-fix-some-cases-of-infinity-and-zero-inputs.patch queue-4.9/mips-math-emu-maddf-msubf-.-d-s-fix-some-cases-of-zero-inputs.patch queue-4.9/mips-math-emu-maddf-msubf-.-d-s-clean-up-maddf_flags-enumeration.patch queue-4.9/mips-math-emu-maddf-msubf-.-d-s-fix-some-cases-of-infinite-inputs.patch