Commit Graph

9 Commits

Author SHA1 Message Date
Michael Kuperstein f0c59330e9 [X86] Make some cast costs more precise
Make some AVX and AVX512 cast costs more precise.
Based on part of a patch by Elena Demikhovsky (D15604).

Differential Revision: http://reviews.llvm.org/D22064

llvm-svn: 275106
2016-07-11 21:39:44 +00:00
Sanjay Patel 04b3496d9b [x86] fix cost of SINT_TO_FP for i32 --> float (PR21356, PR28434)
This is "cvtdq2ps" which does not appear to be particularly slow on any CPU
according to Agner's tables. Choosing "5" as a cost here as suggested in:
https://llvm.org/bugs/show_bug.cgi?id=21356
...but it seems very conservative given that the instruction is fully pipelined,
and I think these costs are supposed to model throughput.

Note that related costs are also most likely too high, but this fixes PR21356
and partly fixes PR28434.

llvm-svn: 274658
2016-07-06 19:15:54 +00:00
Michael Kuperstein aa71bdd3af [TTI] The cost model should not assume vector casts get completely scalarized
The cost model should not assume vector casts get completely scalarized, since
on targets that have vector support, the common case is a partial split up to
the legal vector size. So, when a vector cast  gets split, the resulting casts
end up legal and cheap.

Instead of pessimistically assuming scalarization, base TTI can use the costs
the concrete TTI provides for the split vector, plus a fudge factor to account
for the cost of the split itself. This fudge factor is currently 1 by default,
except on AMDGPU where inserts and extracts are considered free.

Differential Revision: http://reviews.llvm.org/D21251

llvm-svn: 274642
2016-07-06 17:30:56 +00:00
Cong Hou 59898d8c68 [X86][SSE] Update the cost table for integer-integer conversions on SSE2/SSE4.1.
Previously in the conversion cost table there are no entries for integer-integer
conversions on SSE2. This will result in imprecise costs for certain vectorized
operations. This patch adds those entries for SSE2 and SSE4.1. The cost numbers
are counted from the result of running llc on the new test case in this patch.


Differential revision: http://reviews.llvm.org/D15132

llvm-svn: 255315
2015-12-11 00:31:39 +00:00
Elena Demikhovsky a1a40cce9f AVX-512: Updated cost of FP/SINT/UINT conversion operations
I checked and updated the cost of AVX-512 conversion operations. Added cost of conversion operations in DQ mode.
Conversion of illegal types that requires vector split is not calculated right now (like for other X86 targets).

Differential Revision: http://reviews.llvm.org/D15074

llvm-svn: 254494
2015-12-02 08:59:47 +00:00
Simon Pilgrim d862e0f33a [X86][SSE][CostModel] Added full set of sitofp/uitofp costings for SSE2/AVX/AVX2/AVX512F.
Merged separate (but equivalent) SSE2/AVX512F tests.

Removed codegen tests since these are already done better in test/CodeGen/X86.

The actual cost values still need to be updated to match recent codegen improvements.

llvm-svn: 240219
2015-06-20 14:58:01 +00:00
Simon Pilgrim de94fa6438 [X86][SSE][CostModel] Fixed uitofp/sitofp cost target tests to specify sse2/avx2/avx512f directly instead of via a cpu model.
llvm-svn: 240062
2015-06-18 21:26:01 +00:00
Elena Demikhovsky d5e95b57e0 AVX-512: SINT_TO_FP cost model and some bugfixes
Checked some corner cases, for example translation
of <8 x i1> to <8 x double>

llvm-svn: 221883
2014-11-13 11:46:16 +00:00
Arnold Schwaighofer f47d2d7f6b X86 cost model: Model cost for uitofp and sitofp on SSE2
The costs are overfitted so that I can still use the legalization factor.

For example the following kernel has about half the throughput vectorized than
unvectorized when compiled with SSE2. Before this patch we would vectorize it.

unsigned short A[1024];
double B[1024];
void f() {
  int i;
  for (i = 0; i < 1024; ++i) {
    B[i] = (double) A[i];
  }
}

radar://13599001

llvm-svn: 179033
2013-04-08 18:05:48 +00:00