Commit Graph

28 Commits

Author SHA1 Message Date
Alex Richardson 2259ce8c91 [RISC-V] ADDI/ORI/XORI x, 0 should be as cheap as a move
The isTriviallyRematerializable hook is only called for instructions that are
tagged as isAsCheapAsAMove. Since ADDI 0 is used for "mv" it should definitely
be marked with "isAsCheapAsAMove". This change avoids one stack spill in most of
the atomic-rmw.ll tests functions. It also avoids stack spills in two of our
out-of-tree CHERI tests.
ORI/XORI with zero may or may not be the same as a move micro-architecturally,
but since we are already doing it for register == x0, we might as well
do the same if the immediate is zero.

Reviewed By: luismarques

Differential Revision: https://reviews.llvm.org/D86480
2020-08-27 10:32:22 +01:00
Michael Liao e7b920e6fe [DAGCombine] Generalize the case (add (or x, c1), c2) -> (add x, (c1 + c2))
Reviewers: arsenm

Subscribers: sdardis, wdng, hiraditya, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, ecnelises, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81708
2020-06-12 13:53:08 -04:00
Eli Friedman 7c10541e56 [SelectionDAG] Fix usage of Align constructing MachineMemOperands.
The "Align" passed into getMachineMemOperand etc. is the alignment of
the MachinePointerInfo, not the alignment of the memory operation.
(getAlign() on a MachineMemOperand automatically reduces the alignment
to account for this.)

We were passing on wrong (overconservative) alignment in a bunch of
places. Fix a bunch of these, mostly in legalization.  And while I'm
here, switch to the new Align APIs.

The test changes are all scheduling changes: the biggest effect of
preserving large alignments is that it improves alias analysis, so the
scheduler has more freedom.

(I was originally just trying to do a minor cleanup in
SelectionDAGBuilder, but I accidentally went deeper down the rabbit
hole.)

Differential Revision: https://reviews.llvm.org/D77687
2020-04-15 13:01:41 -07:00
Shiva Chen 64f417200e [RISCV] Fix incorrect FP base CFI offset for variable argument functions
When the FP exists, the FP base CFI directive offset should take the size of variable arguments into account.

Differential Revision: https://reviews.llvm.org/D73862
2020-02-10 11:56:08 +08:00
Luís Marques c6b09bff56 [RISCV] Fix wrong CFI directives
Summary: Removes CFI CFA directives that could incorrectly propagate
beyond the basic block they were inteded for. Specifically it removes
the epilogue CFI directives. See the branch_and_tail_call test for an
example of the issue. Should fix the stack unwinding issues caused by
the incorrect directives.

Reviewers: asb, lenary, shiva0217
Reviewed By: lenary
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69723
2019-11-14 18:29:50 +00:00
Luís Marques c5b56caa32 Revert "[RISCV] Fix wrong CFI directives"
test/DebugInfo/RISCV/relax-debug-frame.ll wasn't properly updated.
2019-11-13 13:28:33 +00:00
Luís Marques a5ce8bd715 [RISCV] Fix wrong CFI directives
Summary: Removes CFI CFA directives that could incorrectly propagate
beyond the basic block they were inteded for. Specifically it removes
the epilogue CFI directives. See the branch_and_tail_call test for an
example of the issue. Should fix the stack unwinding issues caused by
the incorrect directives.

Reviewers: asb, lenary, shiva0217
Reviewed By: lenary
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69723
2019-11-13 13:06:15 +00:00
Luís Marques 1c737f54be [RISCV] Fix CFA when doing split sp adjustment with fp
Summary: When using the split sp adjustment and using the frame-pointer
we were still emitting CFI CFA directives based on the sp value. The
final sp-based offset also didn't reflect the two-stage sp adjust. There
remain CFI issues that aren't related to the split sp adjustment, and
thus will be addressed in a separate patch.

Reviewers: asb, lenary, shiva0217
Reviewed By: lenary, shiva0217
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69385
2019-11-10 16:09:14 +00:00
Luís Marques be0fead7bf [RISCV][NFC] Add CFI-related tests
Summary: Adds tests necessary to properly show the impact of other
patches that affect the emission of CFI directives.

Reviewers: asb, lenary
Reviewed By: lenary
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69721
2019-11-10 16:00:07 +00:00
Luis Marques 3d0fbafd0b [RISCV] Switch to the Machine Scheduler
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
2019-09-17 11:15:35 +00:00
Luis Marques 2d550d19b3 Revert Patch from Phabricator
This reverts r372092 (git commit e38695a025)

llvm-svn: 372104
2019-09-17 10:52:09 +00:00
Luis Marques e38695a025 Patch from Phabricator
llvm-svn: 372092
2019-09-17 09:43:08 +00:00
Shiva Chen b12056bd33 [RISCV] Custom legalize i32 operations for RV64 to reduce signed extensions
Differential Revision: https://reviews.llvm.org/D65434

llvm-svn: 367960
2019-08-06 00:24:00 +00:00
Alex Bradbury 0b2803ee65 [RISCV] Add codegen support for ilp32f, ilp32d, lp64f, and lp64d ("hard float") ABIs
This patch adds support for the RISC-V hard float ABIs, building on top of
rL355771, which added basic target-abi parsing and MC layer support. It also
builds on some re-organisations and expansion of the upstream ABI and calling
convention tests which were recently committed directly upstream.

A number of aspects of the RISC-V float hard float ABIs require frontend
support (e.g. flattening of structs and passing int+fp for fp+fp structs in a
pair of registers), and will be addressed in a Clang patch.

As can be seen from the tests, it would be worthwhile extending
RISCVMergeBaseOffsets to handle constant pool as well as global accesses.

Differential Revision: https://reviews.llvm.org/D59357

llvm-svn: 357352
2019-03-30 17:59:30 +00:00
Alex Bradbury b5498cbf64 [RISCV] Add RV64 CHECK lines to test/CodeGen/RISCV/vararg.ll and prepare for hard float tests
vararg.ll previously missed RV64 tests. This patch also prepares for using
vararg.ll to test handling of varargs for the ilp32f/ilp32d/lp64f/lp64d hard
float ABIs. In these ABIs, varargs are passed as in either the ilp32 or lp64
ABI. Due to some slight codegen differences, different check lines are needed
for when RV32D is enabled.

llvm-svn: 357350
2019-03-30 15:53:38 +00:00
Alex Bradbury 98b8ecde64 [RISCV][NFC] Remove floating point operations from test/CodeGen/RISCV/vararg.ll
This minimises differences in output when compiling with hardware floating
point support, which will be done in a future patch (to demonstrate the same
vararg calling convention is used).

llvm-svn: 357339
2019-03-30 05:24:42 +00:00
Alex Bradbury 8a70468a27 [RISCV] Only mark fp as reserved if the function has a dedicated frame pointer
This follows similar logic in the ARM and Mips backends, and allows the free
use of s0 in functions without a dedicated frame pointer. The changes in
callee-saved-gprs.ll most clearly show the effect of this patch.

llvm-svn: 356063
2019-03-13 16:33:45 +00:00
Ana Pazos 05a6064385 Reapply: [RISCV] Set isAsCheapAsAMove for ADDI, ORI, XORI, LUI
This reapplies commit r352010 with RISC-V test fixes.

llvm-svn: 352237
2019-01-25 20:22:49 +00:00
Francis Visoiu Mistrih b7cef81fd3 Replace "no-frame-pointer-*" function attributes with "frame-pointer"
Part of the effort to refactoring frame pointer code generation. We used
to use two function attributes "no-frame-pointer-elim" and
"no-frame-pointer-elim-non-leaf" to represent three kinds of frame
pointer usage: (all) frames use frame pointer, (non-leaf) frames use
frame pointer, (none) frame use frame pointer. This CL makes the idea
explicit by using only one enum function attribute "frame-pointer"

Option "-frame-pointer=" replaces "-disable-fp-elim" for tools such as
llc.

"no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" are still
supported for easy migration to "frame-pointer".

tests are mostly updated with

// replace command line args ‘-disable-fp-elim=false’ with ‘-frame-pointer=none’
grep -iIrnl '\-disable-fp-elim=false' * | xargs sed -i '' -e "s/-disable-fp-elim=false/-frame-pointer=none/g"

// replace command line args ‘-disable-fp-elim’ with ‘-frame-pointer=all’
grep -iIrnl '\-disable-fp-elim' * | xargs sed -i '' -e "s/-disable-fp-elim/-frame-pointer=all/g"

Patch by Yuanfang Chen (tabloid.adroit)!

Differential Revision: https://reviews.llvm.org/D56351

llvm-svn: 351049
2019-01-14 10:55:55 +00:00
Alex Bradbury 686ef92141 [RISCV] Re-generate test/CodeGen/RISCV/vararg.ll after r344142
The improved load-store forwarding committed in r344142 broke this test.

llvm-svn: 344238
2018-10-11 11:11:58 +00:00
Alex Bradbury 90fc100742 [RISCV] Regenerate several tests now enableMultipleCopyHints is enabled by default
r343851 caused codegen changes in several tests. This patch regenerates them.

llvm-svn: 343873
2018-10-05 18:25:55 +00:00
Alex Bradbury a4b7b6dabc [RISCV][NFC] Remove dead CHECK lines from vararg.ll test
The RISCV32 check prefix is no longer used so these lines are dead.

llvm-svn: 343757
2018-10-04 07:35:52 +00:00
Shiva Chen d58bd8dc4a [RISCV] Expand function call to "call" pseudoinstruction
To do this:
1. Change GlobalAddress SDNode to TargetGlobalAddress to avoid legalizer
   split the symbol.

2. Change ExternalSymbol SDNode to TargetExternalSymbol to avoid legalizer
   split the symbol.

3. Let PseudoCALL match direct call with target operand TargetGlobalAddress
   and TargetExternalSymbol.

Differential Revision: https://reviews.llvm.org/D44885

llvm-svn: 330827
2018-04-25 14:19:12 +00:00
Alex Bradbury 3ff2022bb9 [RISCV] Introduce pattern for materialising immediates with 0 for lower 12 bits
These immediates can be materialised with just an lui, rather than an lui+addi 
pair.

llvm-svn: 330293
2018-04-18 20:34:23 +00:00
Alex Bradbury 099c720426 Revert "[RISCV] implement li pseudo instruction"
Reverts rL330224, while issues with the C extension and missed common
subexpression elimination opportunities are addressed. Neither of these issues
are visible in current RISC-V backend unit tests, which clearly need
expanding.

llvm-svn: 330281
2018-04-18 19:02:31 +00:00
Alex Bradbury 480b7bc906 [RISCV] implement li pseudo instruction
The implementation follows the MIPS backend and expands the
pseudo instruction directly during asm parsing. As the result, only
real MC instructions are emitted to the MCStreamer. Additionally,
PseudoLI instructions are emitted during codegen. The actual
expansion to real instructions is performed during MI to MC lowering
and is similar to the expansion performed by the GNU Assembler.

Differential Revision: https://reviews.llvm.org/D41949
Patch by Mario Werner.

llvm-svn: 330224
2018-04-17 21:56:40 +00:00
Alex Bradbury 7d6aa1f7ae [RISCV] Implement frame pointer elimination
llvm-svn: 322839
2018-01-18 11:34:02 +00:00
Alex Bradbury c85be0de56 [RISCV] Support for varargs
Includes support for expanding va_copy. Also adds support for using 'aligned'
registers when necessary for vararg calls, and ensure the frame pointer always
points to the bottom of the vararg spill region. This is necessary to ensure
that the saved return address and stack pointer are always available at fixed
known offsets of the frame pointer.

Differential Revision: https://reviews.llvm.org/D40805

llvm-svn: 322215
2018-01-10 19:41:03 +00:00