If a resource can be held for multiple cycles in the schedule model
then an instruction can be placed into the available queue, another
instruction can be scheduled, but the first will not be taken back out if
the two instructions hazard. To fix this make sure that we update the
available queue even on the first MOp of a cycle, pushing available
instructions back into the pending queue if they now conflict.
This happens with some downstream schedules we have around MVE
instruction scheduling where we use ResourceCycles=[2] to show the
instruction executing over two beats. Apparently the test changes here
are OK too.
Differential Revision: https://reviews.llvm.org/D76909
Summary:
The SPE doesn't have a 'fma' instruction, so the intrinsic becomes a
libcall. It really should become an expansion to two instructions, but
for some reason the compiler doesn't think that's as optimal as a
branch. Since this lowering is done after CTR is allocated for loops,
tell the optimizer that CTR may be used in this case. This prevents a
"Invalid PPC CTR loop!" assertion in the case that a fma() function call
is used in a C/C++ file, and clang converts it into an intrinsic.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D78668
Summary:
Pointed out in a comment for D49754, register spilling will currently
spill SPE registers at almost any offset. However, the instructions
`evstdd` and `evldd` require a) 8-byte alignment, and b) a limit of 256
(unsigned) bytes from the base register, as the offset must fix into a
5-bit offset, which ranges from 0-31 (indexed in double-words).
The update to the register spill test is taken partially from the test
case shown in D49754.
Additionally, pointed out by Kei Thomsen, globals will currently use
evldd/evstdd, though the offset isn't known at compile time, so may
exceed the 8-bit (unsigned) offset permitted. This fixes that as well,
by forcing it to always use evlddx/evstddx when accessing globals.
Part of the patch contributed by Kei Thomsen.
Reviewers: nemanjai, hfinkel, joerg
Subscribers: kbarton, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D54409
llvm-svn: 366318
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
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