projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| dbfa5f4f GKH |
1 | From ddbfff7429a75d954bf5bdff9f2222bceb4c236a Mon Sep 17 00:00:00 2001 |
| 2 | From: Aleksandar Markovic <aleksandar.markovic@imgtec.com> | |
| 3 | Date: Mon, 19 Jun 2017 17:50:12 +0200 | |
| 4 | Subject: MIPS: math-emu: Handle zero accumulator case in MADDF and MSUBF separately | |
| 5 | ||
| 6 | From: Aleksandar Markovic <aleksandar.markovic@imgtec.com> | |
| 7 | ||
| 8 | commit ddbfff7429a75d954bf5bdff9f2222bceb4c236a upstream. | |
| 9 | ||
| 10 | If accumulator value is zero, just return the value of previously | |
| 11 | calculated product. This brings logic in MADDF/MSUBF implementation | |
| 12 | closer to the logic in ADD/SUB case. | |
| 13 | ||
| 14 | Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> | |
| 15 | Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> | |
| 16 | Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> | |
| 17 | Cc: James.Hogan@imgtec.com | |
| 18 | Cc: Paul.Burton@imgtec.com | |
| 19 | Cc: Raghu.Gandham@imgtec.com | |
| 20 | Cc: Leonid.Yegoshin@imgtec.com | |
| 21 | Cc: Douglas.Leung@imgtec.com | |
| 22 | Cc: Petar.Jovanovic@imgtec.com | |
| 23 | Cc: linux-mips@linux-mips.org | |
| 24 | Patchwork: https://patchwork.linux-mips.org/patch/16512/ | |
| 25 | Signed-off-by: Ralf Baechle <ralf@linux-mips.org> | |
| 26 | Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| 27 | ||
| 28 | --- | |
| 29 | arch/mips/math-emu/dp_maddf.c | 5 ++++- | |
| 30 | arch/mips/math-emu/sp_maddf.c | 5 ++++- | |
| 31 | 2 files changed, 8 insertions(+), 2 deletions(-) | |
| 32 | ||
| 33 | --- a/arch/mips/math-emu/dp_maddf.c | |
| 34 | +++ b/arch/mips/math-emu/dp_maddf.c | |
| 35 | @@ -54,7 +54,7 @@ static union ieee754dp _dp_maddf(union i | |
| 36 | return ieee754dp_nanxcpt(z); | |
| 37 | case IEEE754_CLASS_DNORM: | |
| 38 | DPDNORMZ; | |
| 39 | - /* QNAN is handled separately below */ | |
| 40 | + /* QNAN and ZERO cases are handled separately below */ | |
| 41 | } | |
| 42 | ||
| 43 | switch (CLPAIR(xc, yc)) { | |
| 44 | @@ -210,6 +210,9 @@ static union ieee754dp _dp_maddf(union i | |
| 45 | } | |
| 46 | assert(rm & (DP_HIDDEN_BIT << 3)); | |
| 47 | ||
| 48 | + if (zc == IEEE754_CLASS_ZERO) | |
| 49 | + return ieee754dp_format(rs, re, rm); | |
| 50 | + | |
| 51 | /* And now the addition */ | |
| 52 | assert(zm & DP_HIDDEN_BIT); | |
| 53 | ||
| 54 | --- a/arch/mips/math-emu/sp_maddf.c | |
| 55 | +++ b/arch/mips/math-emu/sp_maddf.c | |
| 56 | @@ -54,7 +54,7 @@ static union ieee754sp _sp_maddf(union i | |
| 57 | return ieee754sp_nanxcpt(z); | |
| 58 | case IEEE754_CLASS_DNORM: | |
| 59 | SPDNORMZ; | |
| 60 | - /* QNAN is handled separately below */ | |
| 61 | + /* QNAN and ZERO cases are handled separately below */ | |
| 62 | } | |
| 63 | ||
| 64 | switch (CLPAIR(xc, yc)) { | |
| 65 | @@ -203,6 +203,9 @@ static union ieee754sp _sp_maddf(union i | |
| 66 | } | |
| 67 | assert(rm & (SP_HIDDEN_BIT << 3)); | |
| 68 | ||
| 69 | + if (zc == IEEE754_CLASS_ZERO) | |
| 70 | + return ieee754sp_format(rs, re, rm); | |
| 71 | + | |
| 72 | /* And now the addition */ | |
| 73 | ||
| 74 | assert(zm & SP_HIDDEN_BIT); |