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* util: try to use SSE instructions with MSVC and 32-bit gccBrian Paul2016-08-171-3/+4
| | | | | | | | | | | | | The lrint() and lrintf() functions are pretty slow and make some texture transfers very inefficient. This patch makes a better effort at using those intrisics for 32-bit gcc and MSVC. Note, this patch doesn't address the use of SSE4.1 with MSVC. v2: get rid of the ROUND_WITH_SSE symbol, per Matt. Reviewed-by: José Fonseca <[email protected]> Reviewed-by: Matt Turner <[email protected]>
* util: (trivial) include c99_math.h in rounding.hRoland Scheidegger2015-08-191-2/+1
| | | | Needed for rint/rintf.
* util: Use LONG_MAX instead of LONG_BIT.Jose Fonseca2015-08-101-6/+7
| | | | | | | | | | | More portable. Based on Roland Scheidegger's idea. Tested with roundevent_test on Linux, MinGW, and MSVC. https://bugs.freedesktop.org/show_bug.cgi?id=91591 Reviewed-by: Roland Scheidegger <[email protected]> Reviewed-by: Matt Turner <[email protected]>
* scons: Build roundevent_test.Jose Fonseca2015-08-101-0/+2
| | | | Reviewed-by: Roland Scheidegger <[email protected]>
* util: Cope with LONG_BIT not being defined on Windows.Jose Fonseca2015-08-091-2/+6
| | | | | | | | | | | | Neither MSVC nor MinGW defines LONG_BIT. For MSVC this was not a problem as it doesn't define __x86_64__ macro (it's GCC specific.) However on Windows long type is guaranteed to be 32bits. Also add an #error, as GCC will just warn, not throw any error, when no value is returned. Trivial.
* util: Use SSE intrinsics in _mesa_lroundeven{f,}.Matt Turner2015-08-041-0/+22
| | | | | | | | | | | | | | gcc actually generates this for us now that we use -fno-math-errno (which is weird, since lrintf()/lrint() don't set errno) but clang still does not. Presumably helps MSVC as well. Reduced .text size by 8.5k with gcc before -fno-math-errno. text data bss dec hex filename 4935850 195136 26192 5157178 4eb13a i965_dri.so before 4927225 195128 26192 5148545 4e8f81 i965_dri.so after Reviewed-by: Roland Scheidegger <[email protected]>
* mesa: Replace F_TO_I() with _mesa_lroundevenf().Matt Turner2015-08-031-0/+25
| | | | | | | | | | | I'm not sure what the true meaning of "The rounding mode may vary." is, but it is the case that the IROUND() path rounds differently than the other paths (and does it wrong, at that). Like _mesa_roundeven{f,}(), just add an use _mesa_lroundeven{f,}() that has known semantics. Reviewed-by: Roland Scheidegger <[email protected]>
* util: Optimize _mesa_roundeven with SSE 4.1.Matt Turner2015-03-181-0/+20
| | | | | | | | | | | | The SSE 4.1 ROUND instructions let us implement roundeven directly. Otherwise we assume that the rounding mode has not been modified (as we do in the rest of Mesa) and use rint(). glibc uses the ROUND instruction in rint() after a cpuid check. This patch just lets us inline it directly when we're already building for SSE 4.1. Reviewed-by: Carl Worth <[email protected]>
* mesa: Replace _mesa_round_to_even() with _mesa_roundeven().Matt Turner2015-03-181-0/+58
Eric's initial patch adding constant expression evaluation for ir_unop_round_even used nearbyint. The open-coded _mesa_round_to_even implementation came about without much explanation after a reviewer asked whether nearbyint depended on the application not modifying the rounding mode. Of course (as Eric commented) we rely on the application not changing the rounding mode from its default (round-to-nearest) in many other places, including the IROUND function used by _mesa_round_to_even! Worse, IROUND() is implemented using the trunc(x + 0.5) trick which fails for x = nextafterf(0.5, 0.0). Still worse, _mesa_round_to_even unexpectedly returns an int. I suspect that could cause problems when rounding large integral values not representable as an int in ir_constant_expression.cpp's ir_unop_round_even evaluation. Its use of _mesa_round_to_even is clearly broken for doubles (as noted during review). The constant expression evaluation code for the packing built-in functions also mistakenly assumed that _mesa_round_to_even returned a float, as can be seen by the cast through a signed integer type to an unsigned (since negative float -> unsigned conversions are undefined). rint() and nearbyint() implement the round-half-to-even behavior we want when the rounding mode is set to the default round-to-nearest. The only difference between them is that nearbyint() raises the inexact exception. This patch implements _mesa_roundeven{f,}, a function similar to the roundeven function added by a yet unimplemented technical specification (ISO/IEC TS 18661-1:2014), with a small difference in behavior -- we don't bother raising the inexact exception, which I don't think we care about anyway. At least recent Intel CPUs can quickly change a subset of the bits in the x87 floating-point control register, but the exception mask bits are not included. rint() does not need to change these bits, but nearbyint() does (twice: save old, set new, and restore old) in order to raise the inexact exception, which would incur some penalty. Reviewed-by: Carl Worth <[email protected]>