Revert of skcpu: sse4.1 floor, f16c f16<->f32

Revert of skcpu: sse4.1 floor, f16c f16<->f32 (patchset #10 id:180001 of https://codereview.chromium.org/1891513002/ )

Reason for revert:
Need to change around my #if guards so that clang-cl is treated like GCC and Clang, rather than MSVC.

Original issue's description:
> skcpu: sse4.1 floor, f16c f16<->f32
> 
>   -  floor with roundps is about 4.5x faster when available
>   -  f16 srcover_n is similar to but a little faster than the version in https://codereview.chromium.org/1884683002.  This new one fuses the dst load/stores into the f16<->f32 conversions:
> 
> +0x180	    movups              (%r15), %xmm1
> +0x184	    vcvtph2ps           (%rbx), %xmm2
> +0x189	    movaps              %xmm1, %xmm3
> +0x18c	    shufps              $255, %xmm3, %xmm3
> +0x190	    movaps              %xmm0, %xmm4
> +0x193	    subps               %xmm3, %xmm4
> +0x196	    mulps               %xmm2, %xmm4
> +0x199	    addps               %xmm1, %xmm4
> +0x19c	    vcvtps2ph           $0, %xmm4, (%rbx)
> +0x1a2	    addq                $16, %r15
> +0x1a6	    addq                $8, %rbx
> +0x1aa	    decl                %r14d
> +0x1ad	    jne                 +0x180
> 
> If we decide to land this it'd be a good idea to convert most or all users of SkFloatToHalf_01 and SkHalfToFloat_01 over to the pointer-based versions.
> 
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1891513002
> CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
> 
> Committed: https://skia.googlesource.com/skia/+/cbe3c1af987d622ea67ef560d855b41bb14a0ce9

TBR=fmalita@chromium.org,herb@google.com,reed@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Committed: https://skia.googlesource.com/skia/+/834d9e109298ae704043128005f8c1bc622350f4

[mtklein, 2016-04-14 23:22:59]

Created Revert of skcpu: sse4.1 floor, f16c f16<->f32

[commit-bot: I haz the power, 2016-04-14 23:23:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1891993002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1891993002/1

[commit-bot: I haz the power, 2016-04-14 23:23:18]

Description was changed from

==========
Revert of skcpu: sse4.1 floor, f16c f16<->f32 (patchset #10 id:180001 of
https://codereview.chromium.org/1891513002/ )

Reason for revert:
Need to change around my #if guards so that clang-cl is treated like GCC and
Clang, rather than MSVC.

Original issue's description:
> skcpu: sse4.1 floor, f16c f16<->f32
> 
>   -  floor with roundps is about 4.5x faster when available
>   -  f16 srcover_n is similar to but a little faster than the version in
https://codereview.chromium.org/1884683002.  This new one fuses the dst
load/stores into the f16<->f32 conversions:
> 
> +0x180	    movups              (%r15), %xmm1
> +0x184	    vcvtph2ps           (%rbx), %xmm2
> +0x189	    movaps              %xmm1, %xmm3
> +0x18c	    shufps              $255, %xmm3, %xmm3
> +0x190	    movaps              %xmm0, %xmm4
> +0x193	    subps               %xmm3, %xmm4
> +0x196	    mulps               %xmm2, %xmm4
> +0x199	    addps               %xmm1, %xmm4
> +0x19c	    vcvtps2ph           $0, %xmm4, (%rbx)
> +0x1a2	    addq                $16, %r15
> +0x1a6	    addq                $8, %rbx
> +0x1aa	    decl                %r14d
> +0x1ad	    jne                 +0x180
> 
> If we decide to land this it'd be a good idea to convert most or all users of
SkFloatToHalf_01 and SkHalfToFloat_01 over to the pointer-based versions.
> 
> BUG=skia:
> GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
>
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
> 
> Committed:
https://skia.googlesource.com/skia/+/cbe3c1af987d622ea67ef560d855b41bb14a0ce9

TBR=fmalita@chromium.org,herb@google.com,reed@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:
==========

to

==========
Revert of skcpu: sse4.1 floor, f16c f16<->f32 (patchset #10 id:180001 of
https://codereview.chromium.org/1891513002/ )

Reason for revert:
Need to change around my #if guards so that clang-cl is treated like GCC and
Clang, rather than MSVC.

Original issue's description:
> skcpu: sse4.1 floor, f16c f16<->f32
> 
>   -  floor with roundps is about 4.5x faster when available
>   -  f16 srcover_n is similar to but a little faster than the version in
https://codereview.chromium.org/1884683002.  This new one fuses the dst
load/stores into the f16<->f32 conversions:
> 
> +0x180	    movups              (%r15), %xmm1
> +0x184	    vcvtph2ps           (%rbx), %xmm2
> +0x189	    movaps              %xmm1, %xmm3
> +0x18c	    shufps              $255, %xmm3, %xmm3
> +0x190	    movaps              %xmm0, %xmm4
> +0x193	    subps               %xmm3, %xmm4
> +0x196	    mulps               %xmm2, %xmm4
> +0x199	    addps               %xmm1, %xmm4
> +0x19c	    vcvtps2ph           $0, %xmm4, (%rbx)
> +0x1a2	    addq                $16, %r15
> +0x1a6	    addq                $8, %rbx
> +0x1aa	    decl                %r14d
> +0x1ad	    jne                 +0x180
> 
> If we decide to land this it'd be a good idea to convert most or all users of
SkFloatToHalf_01 and SkHalfToFloat_01 over to the pointer-based versions.
> 
> BUG=skia:
> GOLD_TRYBOT_URL=
https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&is...
>
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
> 
> Committed:
https://skia.googlesource.com/skia/+/cbe3c1af987d622ea67ef560d855b41bb14a0ce9

TBR=fmalita@chromium.org,herb@google.com,reed@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Committed:
https://skia.googlesource.com/skia/+/834d9e109298ae704043128005f8c1bc622350f4
==========

[commit-bot: I haz the power, 2016-04-14 23:23:20]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/834d9e109298ae704043128005f8c1bc622350f4