Commit Graph

7 Commits

Author SHA1 Message Date
Jonas Paulsson b1d014883c [SystemZ::TTI] i8/i16 operands extension costs revisited
Three minor changes to these extra costs:

* For ICmp instructions, instead of adding 2 all the time for extending each
  operand, this is only done if that operand is neither a load or an
  immediate.

* The operands extension costs for divides removed, because we now use a high
  cost already for the divide (20).

* The costs for lhsr/ashr extra costs removed as this did not seem useful.

Review: Ulrich Weigand
https://reviews.llvm.org/D55053

llvm-svn: 347961
2018-11-30 07:09:34 +00:00
Jonas Paulsson 06acb3a236 [SystemZ::TTI] Improve cost for compare of i64 with extended i32 load
CGF/CLGF compares an i64 register with a sign/zero extended loaded i32 value
in memory.

This patch makes such a load considered foldable and so gets a 0 cost.

Review: Ulrich Weigand
https://reviews.llvm.org/D54944

llvm-svn: 347735
2018-11-28 08:58:27 +00:00
Jonas Paulsson d6b7aca911 [SystemZ::TTI] Improve costs for i16 add, sub and mul against memory.
AH, SH and MH costs are already covered in the cases where LHS is 32 bits and
RHS is 16 bits of memory sign-extended to i32.

As these instructions are also used when LHS is i16, this patch recognizes
that the loads will get folded then as well.

Review: Ulrich Weigand
https://reviews.llvm.org/D54940

llvm-svn: 347734
2018-11-28 08:31:50 +00:00
Jonas Paulsson af8e036c29 [SystemZ] Improve isFoldableLoad() for Sub, SDiv and UDiv.
Sub, SDiv and UDiv are not commutative, so only the RHS operand can fold a
load. This patch adds a check for this.

Review: Ulrich Weigand
https://reviews.llvm.org/D53791

llvm-svn: 345596
2018-10-30 13:41:03 +00:00
Jonas Paulsson b7caa809e1 [SystemZ] Improve getMemoryOpCost() to find foldable loads that are converted.
The SystemZ backend can do arithmetic of memory by loading and then extending
one of the operands. Similarly, a load + truncate can be folded into an
operand.

This patch improves the SystemZ TTI cost function to recognize this.

Review: Ulrich Weigand
https://reviews.llvm.org/D52692

llvm-svn: 345327
2018-10-25 22:28:25 +00:00
Jonas Paulsson 4645711a8d [SystemZ] Improve handling and cost estimates of vector integer div/rem
Enable the DAG optimization that converts vector div/rem with constants into
multiply+shifts sequences by expanding them early. This is needed since
ISD::SMUL_LOHI is 'Custom' lowered on SystemZ, and will therefore not be
available to BuildSDIV after legalization.

Better cost values for these instructions based on how they will be
implemented (a constant divisor is cheaper).

Review: Ulrich Weigand
https://reviews.llvm.org/D53196

llvm-svn: 345321
2018-10-25 21:47:22 +00:00
Jonas Paulsson fccc7d66c3 [SystemZ] TargetTransformInfo cost functions implemented.
getArithmeticInstrCost(), getShuffleCost(), getCastInstrCost(),
getCmpSelInstrCost(), getVectorInstrCost(), getMemoryOpCost(),
getInterleavedMemoryOpCost() implemented.

Interleaved access vectorization enabled.

BasicTTIImpl::getCastInstrCost() improved to check for legal extending loads,
in which case the cost of the z/sext instruction becomes 0.

Review: Ulrich Weigand, Renato Golin.
https://reviews.llvm.org/D29631

llvm-svn: 300052
2017-04-12 11:49:08 +00:00