22 Commits

Author SHA1 Message Date
Fangrui Song
eabaee0c59
[RISCV] Omit "@plt" in assembly output "call foo@plt" (#72467)
R_RISCV_CALL/R_RISCV_CALL_PLT distinction is not necessary and
R_RISCV_CALL has been deprecated. Since https://reviews.llvm.org/D132530
`call foo` assembles to R_RISCV_CALL_PLT. The `@plt` suffix is not
useful and can be removed now (matching AArch64 and PowerPC).

GNU assembler assembles `call foo` to RISCV_CALL_PLT since 2022-09
(70f35d72ef04cd23771875c1661c9975044a749c).

Without this patch, unconditionally changing MO_CALL to MO_PLT could
create `jump .L1@plt, a0`, which is invalid in LLVM integrated assembler
and GNU assembler.
2024-01-07 12:09:44 -08:00
Nikita Popov
1456b68686 [RISCV] Convert some tests to opaque pointers (NFC) 2022-12-19 13:01:08 +01:00
Craig Topper
ece4bb5ab8 [RISCV] Teach SExtWRemoval to recognize sign extended values that come from arguments.
This information is not preserved in MIR today. So this patch adds
information to RISCVMachineFunctionInfo when the vreg is created for
the argument.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D134621
2022-10-04 15:39:10 -07:00
Craig Topper
70a64fe7b1 [RISCV] Remove support for the unratified Zbt extension.
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
2022-09-20 20:26:48 -07:00
Craig Topper
6227b7ae31 [RISCV] Move xori creation for scalar setccs to lowering.
This patch enables expansion or custom lowering for some integer
condition codes so that any xori that is needed is created before
the last DAG combine to enable optimization.

I've seen cases where we end up with
(or (xori (setcc), 1), (xori (setcc), 1)) which we would ideally
convert to (xori (and (setcc), (setcc)), 1). This patch doesn't
accomplish that yet, but it should allow us to add DAG
combines as follow ups. Example https://godbolt.org/z/Y4qnvsq1b

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D131729
2022-08-19 13:51:53 -07:00
Craig Topper
f04ae43752 [RISCV] Add more test cases for select with (setge X, C) condition.
InstCombine and SelectionDAG will tend to canonicalize these conditions
to (setgt X, C-1). C-1 might be more costly to materialize than C would
have been.
2022-07-25 11:55:21 -07:00
Liqin Weng
f891123556 [RISCV] Add CMOV isel pattern for (select (setgt X, Imm), Y, Z)
Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D122644
2022-04-07 05:55:53 +00:00
Craig Topper
1e569e3b7b [RISCV] Add CMOV isel pattern for (select (setgt X, -1), Y, Z)
setgt X, -1 is the canonical form of setge X, 0. We can swap the
select operands and use setlt X, X0 when selecting CMOV. This
avoid materializing the -1 in a register.
2022-03-04 22:35:13 -08:00
Hsiangkai Wang
137d3474ca [RISCV] Reverse the order of loading/storing callee-saved registers.
Currently, we restore the return address register as the last restoring
instruction in the epilog. The next instruction is `ret` usually. It is
a use of return address register. In some microarchitectures, there is
load-to-use data hazard. To avoid the load-to-use data hazard, we could
separate the load instruction from its use as far as possible. In this
patch, we reverse the order of restoring callee-saved registers to
increase the distance of `load ra` and `ret` in the epilog.

Differential Revision: https://reviews.llvm.org/D113967
2021-11-22 23:02:11 +08:00
wangpc
af0ecfccae [RISCV] Generate pseudo instruction li
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
2021-11-22 14:01:37 +08:00
Craig Topper
d63f117210 [RISCV] Support RISCVISD::SELECT_CC in ComputeNumSignBitsForTargetNode. 2021-08-13 18:00:09 -07:00
Craig Topper
51151828ac [RISCV] Teach normaliseSetCC to canonicalize X > -1 to X >= 0 and X < 1 to 0 >= X.
This allows the use of BGE with X0 instead of puting -1/1 in a
register.

Reviewed By: jrtc27

Differential Revision: https://reviews.llvm.org/D98542
2021-03-12 11:50:10 -08:00
Craig Topper
d701e37b42 [RISCV] Add test cases for failure to optimize select_cc with X < 1 or X > -1. NFC
We can use BGE with X0 to implement these, but we currently put
1 or -1 into a register.
2021-03-12 11:19:04 -08:00
Michael Munday
4ab0f51a75 Recommit "[RISCV] Legalize select when Zbt extension available"
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
2021-01-21 12:07:44 -08:00
Michael Munday
b42ff9fb03 [RISCV][NFC] Increase test coverage of Zbt extension
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
2021-01-18 17:30:35 +00:00
Alex Bradbury
5dabe03b41 [RISCV][NFC] Add nounwind attribute to functions missing it in test/CodeGen/RISCV
r360897 was incomplete, must have applied an old/wip patch. This is in preparation for emitting CFI directives.

llvm-svn: 361493
2019-05-23 12:43:13 +00:00
Alex Bradbury
7d6aa1f7ae [RISCV] Implement frame pointer elimination
llvm-svn: 322839
2018-01-18 11:34:02 +00:00
Alex Bradbury
e027c93ac2 [RISCV] Implement branch analysis
This is a prerequisite for the branch relaxation pass, and allows a number of
optimisation passes (e.g. BranchFolding and MachineBlockPlacement) to work.

Differential Revision: https://reviews.llvm.org/D40808

llvm-svn: 322222
2018-01-10 20:47:00 +00:00
Alex Bradbury
59136ffab1 [RISCV] Enable emission of alias instructions by default
This patch switches the default for -riscv-no-aliases to false
and updates all affected MC and CodeGen tests. As recommended in
D41071, MC tests use the canonical instructions and the CodeGen
tests use the aliases.

Additionally, for the f and d instructions with rounding mode,
the tests for the aliased versions are moved and tightened such
that they can actually detect if alias emission is enabled.
(see D40902 for context)

Differential Revision: https://reviews.llvm.org/D41225

Patch by Mario Werner.

llvm-svn: 320797
2017-12-15 09:47:01 +00:00
Alex Bradbury
b014e3de52 [RISCV] Implement prolog and epilog insertion
As frame pointer elimination isn't implemented until a later patch and we make 
extensive use of update_llc_test_checks.py, this changes touches a lot of the 
RISC-V tests.

Differential Revision: https://reviews.llvm.org/D39849

llvm-svn: 320357
2017-12-11 12:34:11 +00:00
Francis Visoiu Mistrih
25528d6de7 [CodeGen] Unify MBB reference format in both MIR and debug output
As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
2017-12-04 17:18:51 +00:00
Alex Bradbury
65385167fb [RISCV] Implement lowering of ISD::SELECT
Although ISD::SELECT_CC is a more natural match for RISCVISD::SELECT_CC (and
ultimately the integer RISC-V conditional branch instructions), we choose to
expand ISD::SELECT_CC and lower ISD::SELECT. The appropriate compare+branch
will be created in the case where an ISD::SELECT condition value is created by
an ISD::SETCC node, which operates on XLen types. Other datatypes such as
floating point don't have conditional branch instructions, and lowering
ISD::SELECT allows more flexibility for handling these cases.

Differential Revision: https://reviews.llvm.org/D29937

llvm-svn: 318735
2017-11-21 07:51:32 +00:00