[X86] Check that the type is integer before calling isUnsignedIntSetCC in combineExtSetcc. (#128263)
SETULT can be an unsigned less than integer compare or a unordered less
than FP compare. We need to check the VT to distinguish them.
Fixes on of the issues from #128237.
[DAGCombiner] Reassociate the operands from (OR (OR(CMP1, CMP2)), CMP3) to (OR (OR(CMP1, CMP3)), CMP2)
This happens when CMP1 and CMP3 have the same predicate (or CMP2 and CMP3 have
the same predicate).
This helps optimizations such as the fololowing one:
CMP(A,C)||CMP(B,C) => CMP(MIN/MAX(A,B), C)
CMP(A,C)&&CMP(B,C) => CMP(MIN/MAX(A,B), C)
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D156215
[X86] X86FixupVectorConstantsPass - attempt to replace full width fp vector constant loads with broadcasts on AVX+ targets (REAPPLIED)
lowerBuildVectorAsBroadcast will not broadcast splat constants in all cases, resulting in a lot of situations where a full width vector load that has failed to fold but is loading splat constant values could use a broadcast load instruction just as cheaply, and save constant pool space.
NOTE: SSE3 targets can use MOVDDUP but not all SSE era CPUs can perform this as cheaply as a vector load, we will need to add scheduler model checks if we want to pursue this.
This is an updated commit of 98061013e01207444cfd3980cde17b5e75764fbe after being reverted at a279a09ab9524d1d74ef29b34618102d4b202e2f
Revert rG98061013e01207444cfd3980 - [X86] X86FixupVectorConstantsPass - attempt to replace full width fp vector constant loads with broadcasts on AVX+ targets
Reverting while we address an existing issue exposed by this (Issue #63108)
[X86] X86FixupVectorConstantsPass - attempt to replace full width fp vector constant loads with broadcasts on AVX+ targets
lowerBuildVectorAsBroadcast will not broadcast splat constants in all cases, resulting in a lot of situations where a full width vector load that has failed to fold but is loading splat constant values could use a broadcast load instruction just as cheaply, and save constant pool space.
NOTE: SSE3 targets can use MOVDDUP but not all SSE era CPUs can perform this as cheaply as a vector load, we will need to add scheduler model checks if we want to pursue this.
[MachineCombiner] Use default latency model when no detailed model available
This change adjusts the cost modeling used when the target does not have a schedule model with individual instruction latencies. After this change, we use the default latency information available from TargetSchedule. The default latency information essentially ends up treating most instructions as latency 1, with a few "expensive" ones getting a higher cost.
Previously, we unconditionally applied the first legal pattern - without any consideration of profitability. As a result, this change both prevents some patterns being applied, and changes which patterns are exercised. (i.e. previously the first pattern was applied, afterwards, maybe the second one is because the first wasn't profitable.)
The motivation here is two fold.
First, this brings the default behavior in line with the behavior when -mcpu or -mtune is specified. This improves test coverage, and generally makes it less likely we will have bad surprises when providing more information to the compiler.
Second, this enables some reassociation for ILP by default. Despite being unconditionally enabled, the prior code tended to "reassociate" repeatedly through an entire chain and simply moving the first operand to the end. The result was still a serial chain, just a different one. With this change, one of the intermediate transforms is unprofitable and we end up with a partially flattened tree.
Note that the resulting code diffs show significant room for improvement in the basic algorithm. I am intentionally excluding those from this patch.
For the test diffs, I don't seen any concerning regressions. I took a fairly close look at the RISCV ones, but only skimmed the x86 (particularly vector x86) changes.
Differential Revision: https://reviews.llvm.org/D141017
