Summary:
SPE passes doubles the same as soft-float, in register pairs as i32
types. This is all handled by the target-independent layer. However,
this is not optimal when splitting or reforming the doubles, as it
pushes to the stack and loads from, on either side.
For instance, to pass a double argument to a function, assuming the
double value is in r5, the sequence currently looks like this:
evstdd 5, X(1)
lwz 3, X(1)
lwz 4, X+4(1)
Likewise, to form a double into r5 from args in r3 and r4:
stw 3, X(1)
stw 4, X+4(1)
evldd 5, X(1)
This optimizes the fence to use SPE instructions. Now, to pass a double
to a function:
mr 4, 5
evmergehi 3, 5, 5
And to form a double into r5 from args in r3 and r4:
evmergelo 5, 3, 4
This is comparable to the way that gcc generates the double splits.
This also fixes a bug with expanding builtins to libcalls, where the
LowerCallTo() code path was generating intermediate illegal type nodes.
Reviewers: nemanjai, hfinkel, joerg
Subscribers: kbarton, jfb, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D54583
llvm-svn: 363526
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
There are several Pseudo in PowerPC backend.
eg:
* ISel Pseudo-instructions , which has let usesCustomInserter=1 in td
ExpandISelPseudos -> EmitInstrWithCustomInserter will deal with them.
* Post-RA pseudo instruction, which has let isPseudo = 1 in td, or Standard pseudo (SUBREG_TO_REG,COPY etc.)
ExpandPostRAPseudos -> expandPostRAPseudo will expand them
* Multi-instruction pseudo operations will expand them PPCAsmPrinter::EmitInstruction
* Pseudo instruction in CodeEmitter, which has encoding of 0.
Currently, in td files, especially PPCInstrVSX.td,
we did not distinguish Post-RA pseudo instruction and Pseudo instruction in CodeEmitter very clearly.
This patch is to
* Rename Pseudo<> class to PPCEmitTimePseudo, which means encoding of 0 in CodeEmitter
* Introduce new class PPCPostRAExpPseudo <> for previous PostRA Pseudo
* Introduce new class PPCCustomInserterPseudo <> for previous Isel Pseudo
Differential Revision: https://reviews.llvm.org/D55143
llvm-svn: 349044
Summary:
The Signal Processing Engine (SPE) is found on NXP/Freescale e500v1,
e500v2, and several e200 cores. This adds support targeting the e500v2,
as this is more common than the e500v1, and is in SoCs still on the
market.
This patch is very intrusive because the SPE is binary incompatible with
the traditional FPU. After discussing with others, the cleanest
solution was to make both SPE and FPU features on top of a base PowerPC
subset, so all FPU instructions are now wrapped with HasFPU predicates.
Supported by this are:
* Code generation following the SPE ABI at the LLVM IR level (calling
conventions)
* Single- and Double-precision math at the level supported by the APU.
Still to do:
* Vector operations
* SPE intrinsics
As this changes the Callee-saved register list order, one test, which
tests the precise generated code, was updated to account for the new
register order.
Reviewed by: nemanjai
Differential Revision: https://reviews.llvm.org/D44830
llvm-svn: 337347
This is the lead-up to having SPE codegen. Add the rest of the
instructions, along with MC tests.
Differential Revision: https://reviews.llvm.org/D44829
llvm-svn: 337346