llvm-6502/test/Analysis
Quentin Colombet 8201185d61 [X86] Custom lower UINT_TO_FP from v4f32 to v4i32, and for v8f32 to v8i32 if
AVX2 is available.
According to IACA, the new lowering has a throughput of 8 cycles instead of 13
with the previous one.

Althought this lowering kicks in some SPECs benchmarks, the performance
improvement was within the noise.

Correctness testing has been done for the whole range of uint32_t with the
following program:
    uint4 v = (uint4) {0,1,2,3};
    uint32_t i;
    
    //Check correctness over entire range for uint4 -> float4 conversion
    for( i = 0; i < 1U << (32-2); i++ )
    {
        float4 t = test(v);
        float4 c = correct(v);
        
        if( 0xf != _mm_movemask_ps( t == c ))
        {
            printf( "Error @ %vx: %vf vs. %vf\n", v, c, t);
            return -1;
        }
        
        v += 4;
    }
Where "correct" is the old lowering and "test" the new one.

The patch adds a test case for the two custom lowering instruction.
It also modifies the vector cost model, which is why cast.ll and uitofp.ll are
modified.
2009-02-26-MachineLICMBug.ll is also modified because we now hoist 7
instructions instead of 4 (3 more constant loads).

rdar://problem/18153096>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221657 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-11 02:23:47 +00:00
..
BasicAA Delete -std-compile-opts. 2014-10-16 20:00:02 +00:00
BlockFrequencyInfo
BranchProbabilityInfo
CallGraph
CFLAliasAnalysis
CostModel [X86] Custom lower UINT_TO_FP from v4f32 to v4i32, and for v8f32 to v8i32 if 2014-11-11 02:23:47 +00:00
Delinearization
DependenceAnalysis
Dominators
GlobalsModRef
LazyCallGraph
Lint
LoopInfo
MemoryDependenceAnalysis
PostDominators
RegionInfo
ScalarEvolution Use FileCheck in a few tests. 2014-11-06 15:05:51 +00:00
ScopedNoAliasAA
TypeBasedAliasAnalysis [DSE] Remove no-data-layout-only type-based overlap checking 2014-10-17 11:56:00 +00:00