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AVX: go back to using blend (vs. masked store) when possible.

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All of the masked store calls were inhibiting putting values into
registers, which in turn led to a lot of unnecessary stack traffic.
This approach seems to give better code in the end.
This commit is contained in:
Matt Pharr
2011-09-07 11:26:49 -07:00
parent 375f1cb8e8
commit c86128e8ee
4 changed files with 195 additions and 54 deletions
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113
builtins-avx-x2.ll
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@@ -523,35 +523,104 @@ define void @__masked_store_64(<16 x i64>* nocapture, <16 x i64>,
}
;; FIXME: various code elsewhere in the builtins implementations makes
;; calls to the 32/64 bit versions of these, basically assuming that doing
;; so is faster than doing a full call to an actual masked store, which
;; isn't likely to be the case on AVX. So here we provide those functions
;; but then don't actually do what the caller asked for...
masked_store_blend_8_16_by_16()
declare void @llvm.trap()
define void @__masked_store_blend_8(<8 x i8>* nocapture, <8 x i8>,
<8 x i32>) nounwind alwaysinline {
call void @llvm.trap()
ret void
}
define void @__masked_store_blend_16(<8 x i16>* nocapture, <8 x i16>,
<8 x i32>) nounwind alwaysinline {
call void @llvm.trap()
ret void
}
declare <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float>, <8 x float>,
<8 x float>) nounwind readnone
define void @__masked_store_blend_32(<16 x i32>* nocapture, <16 x i32>,
<16 x i32>) nounwind alwaysinline {
call void @__masked_store_32(<16 x i32> * %0, <16 x i32> %1, <16 x i32> %2)
%maskAsFloat = bitcast <16 x i32> %2 to <16 x float>
%oldValue = load <16 x i32>* %0, align 4
%oldAsFloat = bitcast <16 x i32> %oldValue to <16 x float>
%newAsFloat = bitcast <16 x i32> %1 to <16 x float>
%old0 = shufflevector <16 x float> %oldAsFloat, <16 x float> undef,
<8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%old1 = shufflevector <16 x float> %oldAsFloat, <16 x float> undef,
<8 x i32> <i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
%new0 = shufflevector <16 x float> %newAsFloat, <16 x float> undef,
<8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%new1 = shufflevector <16 x float> %newAsFloat, <16 x float> undef,
<8 x i32> <i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
%mask0 = shufflevector <16 x float> %maskAsFloat, <16 x float> undef,
<8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%mask1 = shufflevector <16 x float> %maskAsFloat, <16 x float> undef,
<8 x i32> <i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
%blend0 = call <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float> %old0,
<8 x float> %new0,
<8 x float> %mask0)
%blend1 = call <8 x float> @llvm.x86.avx.blendv.ps.256(<8 x float> %old1,
<8 x float> %new1,
<8 x float> %mask1)
%blend = shufflevector <8 x float> %blend0, <8 x float> %blend1,
<16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7,
i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
%blendAsInt = bitcast <16 x float> %blend to <16 x i32>
store <16 x i32> %blendAsInt, <16 x i32>* %0, align 4
ret void
}
define void @__masked_store_blend_64(<16 x i64>* nocapture, <16 x i64>,
<16 x i32>) nounwind alwaysinline {
call void @__masked_store_64(<16 x i64> * %0, <16 x i64> %1, <16 x i32> %2)
declare <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double>, <4 x double>,
<4 x double>) nounwind readnone
define void @__masked_store_blend_64(<16 x i64>* nocapture %ptr, <16 x i64> %newi64,
<16 x i32> %mask) nounwind alwaysinline {
%oldValue = load <16 x i64>* %ptr, align 8
%old = bitcast <16 x i64> %oldValue to <16 x double>
%old0d = shufflevector <16 x double> %old, <16 x double> undef,
<4 x i32> <i32 0, i32 1, i32 2, i32 3>
%old1d = shufflevector <16 x double> %old, <16 x double> undef,
<4 x i32> <i32 4, i32 5, i32 6, i32 7>
%old2d = shufflevector <16 x double> %old, <16 x double> undef,
<4 x i32> <i32 8, i32 9, i32 10, i32 11>
%old3d = shufflevector <16 x double> %old, <16 x double> undef,
<4 x i32> <i32 12, i32 13, i32 14, i32 15>
%new = bitcast <16 x i64> %newi64 to <16 x double>
%new0d = shufflevector <16 x double> %new, <16 x double> undef,
<4 x i32> <i32 0, i32 1, i32 2, i32 3>
%new1d = shufflevector <16 x double> %new, <16 x double> undef,
<4 x i32> <i32 4, i32 5, i32 6, i32 7>
%new2d = shufflevector <16 x double> %new, <16 x double> undef,
<4 x i32> <i32 8, i32 9, i32 10, i32 11>
%new3d = shufflevector <16 x double> %new, <16 x double> undef,
<4 x i32> <i32 12, i32 13, i32 14, i32 15>
%mask0 = shufflevector <16 x i32> %mask, <16 x i32> undef,
<8 x i32> <i32 0, i32 0, i32 1, i32 1, i32 2, i32 2, i32 3, i32 3>
%mask1 = shufflevector <16 x i32> %mask, <16 x i32> undef,
<8 x i32> <i32 4, i32 4, i32 5, i32 5, i32 6, i32 6, i32 7, i32 7>
%mask2 = shufflevector <16 x i32> %mask, <16 x i32> undef,
<8 x i32> <i32 8, i32 8, i32 9, i32 9, i32 10, i32 10, i32 11, i32 11>
%mask3 = shufflevector <16 x i32> %mask, <16 x i32> undef,
<8 x i32> <i32 12, i32 12, i32 13, i32 13, i32 14, i32 14, i32 15, i32 15>
%mask0d = bitcast <8 x i32> %mask0 to <4 x double>
%mask1d = bitcast <8 x i32> %mask1 to <4 x double>
%mask2d = bitcast <8 x i32> %mask2 to <4 x double>
%mask3d = bitcast <8 x i32> %mask3 to <4 x double>
%result0d = call <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double> %old0d,
<4 x double> %new0d, <4 x double> %mask0d)
%result1d = call <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double> %old1d,
<4 x double> %new1d, <4 x double> %mask1d)
%result2d = call <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double> %old2d,
<4 x double> %new2d, <4 x double> %mask2d)
%result3d = call <4 x double> @llvm.x86.avx.blendv.pd.256(<4 x double> %old3d,
<4 x double> %new3d, <4 x double> %mask3d)
%result01 = shufflevector <4 x double> %result0d, <4 x double> %result1d,
<8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%result23 = shufflevector <4 x double> %result2d, <4 x double> %result3d,
<8 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7>
%result = shufflevector <8 x double> %result01, <8 x double> %result23,
<16 x i32> <i32 0, i32 1, i32 2, i32 3, i32 4, i32 5, i32 6, i32 7,
i32 8, i32 9, i32 10, i32 11, i32 12, i32 13, i32 14, i32 15>
%result64 = bitcast <16 x double> %result to <16 x i64>
store <16 x i64> %result64, <16 x i64> * %ptr
ret void
}