SM1 dp2add doesn't map src swizzles to the dst writemask, also it
expects the last argument to have a replicate swizzle.
Before this patch we were writing the operation as:
```
dp2add r0.x, r1.x, r0.x, r2.x
```
and now it is:
```
dp2add r0.x, r1.xyxx, r0.xyxx, r2.x
```
dp2add now has its own function, write_sm1_dp2add(), since it seems to
be the only instruction with this structure.
Ideally we would be using the default swizzles for the first two src
arguments:
```
dp2add r0.x, r1, r0, r2.x
```
since, according to native's documentation, these are supported for all
sm < 4.
But this change -- along with following the convention of repeating the
last component of the swizzle when fewer than 4 components are to be
specified -- would require more global changes, probably in
hlsl_swizzle_from_writemask() and hlsl_map_swizzle().
Because of the change introduced in
f21693b2 vkd3d-shader/hlsl: Use reg_size as component count when allocating a single register.
SM1 scalars and vectors were not longer getting the correct writemask
when they are allocated.
This happened because they have to reserve the whole register even if
they only use some of its components, so their reg_size may differ from
the number of components.
This commit fixes that.
Prevent them from being ever looked up.
Our naming scheme for synthetic variables already effectively prevents this, but
this is better for clarity. We also will need to be able to move some named
variables into a dummy scope to account for complexities around function
definition and declarations.
Co-authored-by: Francisco Casas <fcasas@codeweavers.com>
Co-authored-by: Zebediah Figura <zfigura@codeweavers.com>
Because copy_propagation_transform_object_load() replaces a deref
instead of an instruction, it is currently prone to two problems:
1- It can replace a deref with the same deref, returning true every
time and getting the compilation stuck in an endless loop of
copy-propagation iterations.
2- When performed multiple times in the same deref, the second time it
can replace the deref with a deref from a temp that is only valid in
another point of the program execution, resulting in an incorrect value.
This patch preempts this by avoiding replacing derefs when the new deref
doesn't point to a uniform variable. Because, uniform variables cannot
be written to.
Reinterpret min16float, min10float, min16int, min12int, and min16uint
as their regular counterparts: float, float, int, int, uint,
respectively.
A proper implementation would require adding minimum precision
indicators to all the dxbc-tpf instructions that use these types.
Consider the output of fxc 10.1 with the following shader:
uniform int i;
float4 main() : sv_target
{
min16float4 a = {0, 1, 2, i};
min16int2 b = {4, i};
min10float3 c = {6.4, 7, i};
min12int d = 9.4;
min16uint4x2 e = {14.4, 15, 16, 17, 18, 19, 20, i};
return mul(e, b) + a + c.xyzx + d;
}
However, if the graphics driver doesn't have minimum precision support,
it ignores the minimum precision indicators and runs at 32-bit
precision, which is equivalent as working with regular types.
If the offset of a gather resource load can be represented as an
aoffimmi (vectori of ints from -8 to 7), use one.
This is of particular importance for 4.0 profiles, where this is the only
valid way of representing offsets for this operation.
If a hlsl_ir_load loads a variable whose components are stored from different
instructions, copy propagation doesn't replace it.
But if all these instructions are constants (which currently is the case
for value constructors), the load could be replaced with a constant value.
Which is expected in some other instructions, e.g. texel_offsets when
using aoffimmi modifiers.
For instance, this shader:
```
sampler s;
Texture2D t;
float4 main() : sv_target
{
return t.Gather(s, float2(0.6, 0.6), int2(0, 0));
}
```
results in the following IR before applying the patch:
```
float | 6.00000024e-01
float | 6.00000024e-01
uint | 0
| = (<constructor-2>[@4].x @2)
uint | 1
| = (<constructor-2>[@6].x @3)
float2 | <constructor-2>
int | 0
int | 0
uint | 0
| = (<constructor-5>[@11].x @9)
uint | 1
| = (<constructor-5>[@13].x @10)
int2 | <constructor-5>
float4 | gather_red(resource = t, sampler = s, coords = @8, offset = @15)
| return
| = (<output-sv_target0> @16)
```
and this IR afterwards:
```
float2 | {6.00000024e-01 6.00000024e-01 }
int2 | {0 0 }
float4 | gather_red(resource = t, sampler = s, coords = @2, offset = @3)
| return
| = (<output-sv_target0> @4)
```
Rename it to copy_propagation_replace_with_single_instr() accordingly.
The idea is to introduce a constant vector replacement pass which will do the
same thing.
copy_propagation_compute_replacement() is not doing very much for us, and
conceptually is a bit of an odd fit anyway, since it's meant to deal with
multi-component types.
