We don't have very many compressible FP instructions, just load and store.
These instruction require the FP register to be f8-f15.
This patch changes the FP allocation order to prioritize f10-f15 first.
These are also the FP argument registers. So I allocated them in reverse
order starting at f15 to avoid taking the first argument registers.
This appears to match gcc allocation order.
Reviewed By: asb
Differential Revision: https://reviews.llvm.org/D146488
Like what has been done in AArch64 (D125335).
We enable this under `-O2` to show the codegen diffs here but we
may only do this under `-O3` like AArch64.
There are two cases that we may produce these eliminable copies:
1. ISel of `FrameIndex`. Like `rvv/fixed-vectors-calling-conv.ll`.
2. Tail duplication. Like `select-optimize-multiple.ll`.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D144535
Compressed instructions usually require one of the source registers
to also be the source register. The register allocator doesn't have
that bias on its own.
This patch adds register allocation hints to introduce this bias.
I've started with ADDI, ADDIW, and SLLI. These all have a 5-bit
field for the register. If the source and dest register are the
same they are guaranteed to compress as long as the immediate is
also 6 bits.
This code was inspired by similar code from the SystemZ target.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D138242
This extension does not appear to be on its way to ratification.
Out of the unratified bitmanip extensions, this one had the
largest impact on the compiler.
Posting this patch to start a discussion about whether we should
remove these extensions. We'll talk more at the RISC-V sync meeting this
Thursday.
Reviewed By: asb, reames
Differential Revision: https://reviews.llvm.org/D133834
Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D127871
Including the following opcode:
Select_FPR16_Using_CC_GPR
Select_FPR32_Using_CC_GPR
Select_FPR64_Using_CC_GPR
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D127871
Clang computes the default ABI if -mabi is empty
and encode it in LLVM IR module flag since D105555.
For correctness, llc need to give the same target-abi
(Options.MCOptions.ABIName) with ABI encoded in IR.
The getSubtargetImpl already has a check for them only if
Options.MCOptions.ABIName is not empty.
In order to get more robustness we could have a check for
explicit ABI, but now we have two different logic to
compute the default ABI.
The front-end ABI is defautl to the ilp32/ilp32e/lp64, and
ilp32d/lp64d when hardware support for extension D.
The backend ABI is default to the ilp32/ilp32e/lp64.
Reviewed by: asb, jrtc27
Differential Revision: https://reviews.llvm.org/D118333
After D86836, we can define multiple cost values for
different cost models. So here we set CostPerUse to
1 iff RVC is enabled to avoid potential impact on RA.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D117741
Add an alias of `addi [x], zero, imm` to generate pseudo
instruction li, which makes assembly mush more readable.
For existed tests, users can update them by running script
`llvm/utils/update_llc_test_checks.py`.
Reviewed By: asb
Differential Revision: https://reviews.llvm.org/D112692
Similar to our free standing setcc patterns, we can use ADDI to
subtract the immediate from the other operand. Then the cmov
can check if the result is zero or non-zero.
Reviewed By: mundaym
Differential Revision: https://reviews.llvm.org/D95169
This recommits 71ed4b6ce57d8843ef705af8f98305976a8f107a with
the polarity of some of the pattern corrected.
Original commit message:
The custom expansion of select operations in the RISC-V backend
interferes with the matching of cmov instructions. Legalizing
select when the Zbt extension is available solves that problem.
Reviewed By: luismarques, craig.topper
Differential Revision: https://reviews.llvm.org/D93767
Add Zbt (ternary) extension code generation to the select lowering
tests since it can have a significant impact on how select is
lowered.
While we are here make the neg-abs commands more consistent with
the other tests.
Reviewed By: lenary
Differential Revision: https://reviews.llvm.org/D94798
Most of the test changes are trivial instruction reorderings and differing
register allocations, without any obvious performance impact.
Differential Revision: https://reviews.llvm.org/D66973
llvm-svn: 372106
This patch optimizes the emission of a sequence of SELECTs with the same
condition, avoiding the insertion of unnecessary control flow. Such a sequence
often occurs when a SELECT of values wider than XLEN is legalized into two
SELECTs with legal types. We have identified several use cases where the
SELECTs could be interleaved with other instructions. Therefore, we extend the
sequence to include non-SELECT instructions if we are able to detect that the
non-SELECT instructions do not impact the optimization.
This patch supersedes https://reviews.llvm.org/D59096, which attempted to
address this issue by introducing a new SelectionDAG node. Hat tip to Eli
Friedman for his feedback on how to best handle this issue.
Differential Revision: https://reviews.llvm.org/D59355
Patch by Luís Marques.
llvm-svn: 356741
