Arnold Schwaighofer 5f0d9dbdf4 X86 cost model: Adjust cost for custom lowered vector multiplies ... This matters for example in following matrix multiply: int **mmult(int rows, int cols, int **m1, int **m2, int **m3) { int i, j, k, val; for (i=0; i<rows; i++) { for (j=0; j<cols; j++) { val = 0; for (k=0; k<cols; k++) { val += m1[i][k] * m2[k][j]; } m3[i][j] = val; } } return(m3); } Taken from the test-suite benchmark Shootout. We estimate the cost of the multiply to be 2 while we generate 9 instructions for it and end up being quite a bit slower than the scalar version (48% on my machine). Also, properly differentiate between avx1 and avx2. On avx-1 we still split the vector into 2 128bits and handle the subvector muls like above with 9 instructions. Only on avx-2 will we have a cost of 9 for v4i64. I changed the test case in test/Transforms/LoopVectorize/X86/avx1.ll to use an add instead of a mul because with a mul we now no longer vectorize. I did verify that the mul would be indeed more expensive when vectorized with 3 kernels: for (i ...) r += a[i] * 3; for (i ...) m1[i] = m1[i] * 3; // This matches the test case in avx1.ll and a matrix multiply. In each case the vectorized version was considerably slower. radar://13304919 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176403 91177308-0d34-0410-b5e6-96231b3b80d8		2013-03-02 04:02:52 +00:00
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arith.ll	X86 cost model: Adjust cost for custom lowered vector multiplies	2013-03-02 04:02:52 +00:00
cast.ll	I optimized the following patterns:	2013-02-20 12:42:54 +00:00
cmp.ll	Reverse order of checking SSE level when calculating compare cost, so we check	2012-12-18 22:57:56 +00:00
gep.ll	ARM cost model: Address computation in vector mem ops not free	2013-02-08 14:50:48 +00:00
i32.ll	We are not ready to estimate the cost of integer expansions based on the number of parts. This test is too noisy.	2012-12-23 09:11:07 +00:00
insert-extract-at-zero.ll	Cost Model: Normalize the insert/extract index when splitting types	2012-11-05 21:12:13 +00:00
intrinsic-cost.ll	Cost model support for lowered math builtins.	2013-02-28 19:09:33 +00:00
lit.local.cfg
load_store.ll	Improve the X86 cost model for loads and stores.	2012-12-21 01:33:59 +00:00
loop_v2.ll
tiny.ll	Cost Model: change the default cost of control flow instructions (br / ret / ...) to zero.	2012-12-05 21:21:26 +00:00
vectorized-loop.ll	Improve the X86 cost model for loads and stores.	2012-12-21 01:33:59 +00:00