Since 32-bit instructions with 32-bit input immediate behavior
are used to materialize 16-bit constants in 32-bit registers
for 16-bit instructions, determining the legality based
on the size is incorrect. Change operands to have the size
specified in the type.
Also adds a workaround for a disassembler bug that
produces an immediate MCOperand for an operand that
is supposed to be OPERAND_REGISTER.
The assembler appears to accept out of bounds immediates and
truncates them, but this seems to be an issue for 32-bit
already.
llvm-svn: 289306
Not having this legal led to combine failures, resulting
in dumb things like bitcasts of constants not being folded
away.
The only reason I'm leaving the v_mov_b32 hack that f32
already uses is to avoid madak formation test regressions.
PeepholeOptimizer has an ordering issue where the immediate
fold attempt is into the sgpr->vgpr copy instead of the actual
use. Running it twice avoids that problem.
llvm-svn: 289096
Structure the definitions a bit more like the other classes.
The main change here is to split EXP with the done bit set
to a separate opcode, so we can set mayLoad = 1 so that it won't
be reordered before the other exp stores, since this has the special
constraint that if the done bit is set then this should be the last
exp in she shader.
Previously all exp instructions were inferred to have unmodeled
side effects.
llvm-svn: 288695
The wave barrier represents the discardable barrier. Its main purpose is to
carry convergent attribute, thus preventing illegal CFG optimizations. All lanes
in a wave come to convergence point simultaneously with SIMT, thus no special
instruction is needed in the ISA. The barrier is discarded during code generation.
Differential Revision: https://reviews.llvm.org/D26585
llvm-svn: 287007
This is the conservatively correct way because it's easy to
move or replace a scalar immediate. This was incorrect in the case
when the register class wasn't known from the static instruction
definition, but still needed to be an SGPR. The main example of this
is inlineasm has an SGPR constraint.
Also start verifying the register classes of inlineasm operands.
llvm-svn: 285762
For some reason there are both of these available, except
for scalar 64-bit compares which only has u64. I'm not sure
why there are both (I'm guessing it's for the one bit inputs we
don't use), but for consistency always using the
unsigned one.
llvm-svn: 282832
Fixes to allow spilling all registers at the end of the block
work with exec modifications. Don't emit s_and_saveexec_b64 for
if lowering, and instead emit copies. Mark control flow mask
instructions as terminators to get correct spill code placement
with fast regalloc, and then have a separate optimization pass
form the saveexec.
This should work if SGPRs are spilled to VGPRs, but
will likely fail in the case that an SGPR spills to memory
and no workitem takes a divergent branch.
llvm-svn: 282667
We were trying to avoid using a FrameIndex operand in non-pointer
operands in a convoluted way, and would break because of
using TargetFrameIndex. The TargetFrameIndex should only be used
in the case where it makes sense to fold it as part of the addressing
mode, otherwise it requires materialization like a normal constant.
This wasn't working reliably and failed in the added testcase, hitting
the assert when processing the frame index.
The TargetFrameIndex was coming from trying to produce an AssertZext
limiting the maximum stack size. I'm not sure this was correct to begin
with, because it is apparently possible to have a single workitem
dispatch that requires all 4G of private memory.
llvm-svn: 281824
These clean up some unnecessary or instructions in
cases with complex loops.
In the original testcase I noticed this, the same
or with exec was repeated 5 or 6 times in a row. With
this only one is emitted or sometimes a copy.
llvm-svn: 281786
This addresses a TODO to handle operations besides and. This
also starts eliminating no-op operations with a constant that
can emerge later.
llvm-svn: 281488
If the literal is being folded into src0, it doesn't matter
if it's an SGPR because it's being replaced with the literal.
Also fixes initially selecting 32-bit versions of some instructions
which also confused commuting.
llvm-svn: 281117
Summary:
Prevously assembler parsed all literals as either 32-bit integers or 32-bit floating-point values. Because of this we couldn't support f64 literals.
E.g. in instruction "v_fract_f64 v[0:1], 0.5", literal 0.5 was encoded as 32-bit literal 0x3f000000, which is incorrect and will be interpreted as 3.0517578125E-5 instead of 0.5. Correct encoding is inline constant 240 (optimal) or 32-bit literal 0x3FE00000 at least.
With this change the way immediate literals are parsed is changed. All literals are always parsed as 64-bit values either integer or floating-point. Then we convert parsed literals to correct form based on information about type of operand parsed (was literal floating or binary) and type of expected instruction operands (is this f32/64 or b32/64 instruction).
Here are rules how we convert literals:
- We parsed fp literal:
- Instruction expects 64-bit operand:
- If parsed literal is inlinable (e.g. v_fract_f64_e32 v[0:1], 0.5)
- then we do nothing this literal
- Else if literal is not-inlinable but instruction requires to inline it (e.g. this is e64 encoding, v_fract_f64_e64 v[0:1], 1.5)
- report error
- Else literal is not-inlinable but we can encode it as additional 32-bit literal constant
- If instruction expect fp operand type (f64)
- Check if low 32 bits of literal are zeroes (e.g. v_fract_f64 v[0:1], 1.5)
- If so then do nothing
- Else (e.g. v_fract_f64 v[0:1], 3.1415)
- report warning that low 32 bits will be set to zeroes and precision will be lost
- set low 32 bits of literal to zeroes
- Instruction expects integer operand type (e.g. s_mov_b64_e32 s[0:1], 1.5)
- report error as it is unclear how to encode this literal
- Instruction expects 32-bit operand:
- Convert parsed 64 bit fp literal to 32 bit fp. Allow lose of precision but not overflow or underflow
- Is this literal inlinable and are we required to inline literal (e.g. v_trunc_f32_e64 v0, 0.5)
- do nothing
- Else report error
- Do nothing. We can encode any other 32-bit fp literal (e.g. v_trunc_f32 v0, 10000000.0)
- Parsed binary literal:
- Is this literal inlinable (e.g. v_trunc_f32_e32 v0, 35)
- do nothing
- Else, are we required to inline this literal (e.g. v_trunc_f32_e64 v0, 35)
- report error
- Else, literal is not-inlinable and we are not required to inline it
- Are high 32 bit of literal zeroes or same as sign bit (32 bit)
- do nothing (e.g. v_trunc_f32 v0, 0xdeadbeef)
- Else
- report error (e.g. v_trunc_f32 v0, 0x123456789abcdef0)
For this change it is required that we know operand types of instruction (are they f32/64 or b32/64). I added several new register operands (they extend previous register operands) and set operand types to corresponding types:
'''
enum OperandType {
OPERAND_REG_IMM32_INT,
OPERAND_REG_IMM32_FP,
OPERAND_REG_INLINE_C_INT,
OPERAND_REG_INLINE_C_FP,
}
'''
This is not working yet:
- Several tests are failing
- Problems with predicate methods for inline immediates
- LLVM generated assembler parts try to select e64 encoding before e32.
More changes are required for several AsmOperands.
Reviewers: vpykhtin, tstellarAMD
Subscribers: arsenm, kzhuravl, artem.tamazov
Differential Revision: https://reviews.llvm.org/D22922
llvm-svn: 281050
Summary:
This fixes a rare bug in polygon stippling with non-monolithic pixel shaders.
The underlying problem is as follows: the prolog part contains the polygon
stippling sequence, i.e. a kill. The main part then enables WQM based on the
_reduced_ exec mask, effectively undoing most of the polygon stippling.
Since we cannot know whether polygon stippling will be used, the main part
of a non-monolithic shader must always return to exact mode to fix this
problem.
Reviewers: arsenm, tstellarAMD, mareko
Subscribers: arsenm, llvm-commits, kzhuravl
Differential Revision: https://reviews.llvm.org/D23131
llvm-svn: 280589
readlane/writelane do not support using m0 as the output/input.
Constrain the register class of spill vregs to try to avoid this,
but also handle spilling of the physreg when necessary by inserting
an additional copy to a normal SGPR.
llvm-svn: 280584
Summary:
Created a new td file MIMGInstructions.td which contains all definitions
of MIMG related instructions.
Reviewed by:
kzhuravl, vpykhtin
Differential Revision:
http://reviews.llvm.org/D24106
llvm-svn: 280385
There's only one use of this for the convenience
of a pattern. I think v_mov_b64_pseudo should also be
moved, but SIFoldOperands does currently make use of it.
llvm-svn: 279901
It isn't used for anything, and is also misleading since
it could be spilled at the end of the block, so it can't be relied
on. There ends up being a verifier error about using an undefined
register since the spill kills the register.
llvm-svn: 279899
Summary:
This patch implements readlane/readfirstlane intrinsics.
TODO: need to define a new register class to consider the case
that the source could be a vector register or M0.
Reviewed by:
arsenm and tstellarAMD
Differential Revision:
http://reviews.llvm.org/D22489
llvm-svn: 279660
Do most of the lowering in a pre-RA pass. Keep the skip jump
insertion late, plus a few other things that require more
work to move out.
One concern I have is now there may be COPY instructions
which do not have the necessary implicit exec uses
if they will be lowered to v_mov_b32.
This has a positive effect on SGPR usage in shader-db.
llvm-svn: 279464
