search for: blendps

On Tuesday 16 June 2009 19:35, David Greene wrote: > So which is more intuitive and less error-prone? > > defm BLENDPS : sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0C, > i32i8imm, "blend", "blend", "f32", 4>; > > or > > defm BLENDPS : sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0C, > i32i8imm, "b...

...2 : X86ValueType { let VT = v4f32; let RegClass = VR128; let suffix = "ps"; } class X86_v8f32 : X86ValueType { let VT = v8f32; let RegClass = VR256; let suffix = "ps"; } Ok, you get the picture. Now let's look at how we would write instruction patterns: defm BLENDPS : sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0C, i32i8imm, "blend", "blend", "f32">; defm BLENDPD : sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0D, i32i8imm, "blend", "blend", &qu...

On Jun 16, 2009, at 5:49 PM, David Greene wrote: > On Tuesday 16 June 2009 19:35, David Greene wrote: > >> So which is more intuitive and less error-prone? >> >> defm BLENDPS : >> sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0C, >> i32i8imm, "blend", "blend", "f32", 4>; >> >> or >> >> defm BLENDPS : >> sse41_avx_fp_binary_vector_osta_vintrinsic_rmi_rrmi<0x0C,...

On Jun 15, 2009, at 11:33 AM, David Greene wrote: > To reduce redundancy, developers must be able to write generic > patterns > like this: > > [(set DSTREGCLASS:$dst, // rr, rrr > (xor (INTSRCTYPE (bitconvert (SRCTYPE SRCREGCLASS:$src1))), > (INTSRCTYPE (bitconvert (SRCTYPE SRCREGCLASS:$src2)))))], > > The substitution then fills in the appropriate types,

Chris Lattner wrote: > However, I don't see any reason to base this off of strings. Instead > of passing down "f32" as a string, why not do something like this > pseudo code: > > class X86ValueType { > RegisterClass RegClass; > ... > } > > def X86_f32 : X86ValueType { > let RegClass = FR32; > ... }; > def X86_i32 :

...citly said that we currently lack of SSE4.1 blend support. Unfortunately, this seems to be one of the main reasons for the slowdown we are seeing. Here is a list of what we found so far that we think is causing most of the slowdown: 1) shufps is always emitted in cases where we could emit a single blendps; in these cases, blendps is preferable because it has better reciprocal throughput (this is true on all modern Intel and AMD cpus). Things get worse when it comes to lowering shuffles where the shuffle mask indices refer to elements from both input vectors in each lane. For example, a shuffle mask...

...gt; of SSE4.1 blend support. Unfortunately, this seems to be one of the > main reasons for the slowdown we are seeing. > > Here is a list of what we found so far that we think is causing most > of the slowdown: > 1) shufps is always emitted in cases where we could emit a single > blendps; in these cases, blendps is preferable because it has better > reciprocal throughput (this is true on all modern Intel and AMD cpus). > > Yep. I think this is actually super easy. I'll add support for blendps shortly. > > > Things get worse when it comes to lowering shuffl...

...port. Unfortunately, this seems to be one of the >> main reasons for the slowdown we are seeing. >> >> Here is a list of what we found so far that we think is causing most >> of the slowdown: >> 1) shufps is always emitted in cases where we could emit a single >> blendps; in these cases, blendps is preferable because it has better >> reciprocal throughput (this is true on all modern Intel and AMD cpus). > > > Yep. I think this is actually super easy. I'll add support for blendps > shortly. Thanks Chandler! > >> 3) When a shuffle per...

...ort. Unfortunately, this seems to be one of the >> main reasons for the slowdown we are seeing. >> >> Here is a list of what we found so far that we think is causing most >> of the slowdown: >> 1) shufps is always emitted in cases where we could emit a single >> blendps; in these cases, blendps is preferable because it has better >> reciprocal throughput (this is true on all modern Intel and AMD cpus). >> >> Things get worse when it comes to lowering shuffles where the shuffle >> mask indices refer to elements from both input vectors in ea...

...4 x float> %2 >>> } >>> >>> >>> llc -march=x86-64 -mattr=+avx test.ll -o - >>> >>> test: # @test >>> vxorps %xmm2, %xmm2, %xmm2 >>> vmovss %xmm0, %xmm2, %xmm2 >>> vblendps $4, %xmm0, %xmm2, %xmm0 # xmm0 = xmm2[0,1],xmm0[2],xmm2[3] >>> vinsertps $48, %xmm1, %xmm0, %xmm0 # xmm0 = xmm0[0,1,2],xmm1[0] >>> retl >>> >>> test2: # @test2 >>> vinsertps $48, %xmm1, %xmm0, %xmm0 # x...