freedreno/turnip: Use the NIR info to decide if we need helper invocations.

We had an approximation that was assuming any ddx or tex instruction
needed helper invocations, but that's not true for texelFetch() or
textureSize().  It also meant that we were setting PIXLOD on vertex and
compute shaders doing texturing, which doesn't really make sense.

shader-db (with a hack to log pixlod):
total pixlod in shared programs: 582 -> 573 (-1.55%)

Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2681
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4308>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4308>

diff --git a/src/freedreno/ir3/ir3_compiler_nir.c b/src/freedreno/ir3/ir3_compiler_nir.c
index cf70ae5b4f620131406ec21723488a51ea06bcc7..a24605bd7149b4bd8fd4a936aa72d18d95dcb899 100644 (file)
--- a/src/freedreno/ir3/ir3_compiler_nir.c
+++ b/src/freedreno/ir3/ir3_compiler_nir.c
@@ -3543,6 +3543,10 @@ ir3_compile_shader_nir(struct ir3_compiler *compiler,
        /* Collect sampling instructions eligible for pre-dispatch. */
        collect_tex_prefetches(ctx, ir);
 
+       if (so->type == MESA_SHADER_FRAGMENT &&
+                       ctx->s->info.fs.needs_helper_invocations)
+               so->need_pixlod = true;
+
 out:
        if (ret) {
                if (so->ir)

diff --git a/src/freedreno/ir3/ir3_legalize.c b/src/freedreno/ir3/ir3_legalize.c
index d88ef00d28a52392f43fcf07f0b1c4acf1338d7c..bed8cd1c03a8df9c88bd31ea73f8f9200f08ef84 100644 (file)
--- a/src/freedreno/ir3/ir3_legalize.c
+++ b/src/freedreno/ir3/ir3_legalize.c
@@ -239,7 +239,6 @@ legalize_block(struct ir3_legalize_ctx *ctx, struct ir3_block *block)
 
                if (is_tex_or_prefetch(n)) {
                        regmask_set(&state->needs_sy, n->regs[0]);
-                       ctx->so->need_pixlod = true;
                        if (n->opc == OPC_META_TEX_PREFETCH)
                                has_tex_prefetch = true;
                } else if (n->opc == OPC_RESINFO) {

diff --git a/src/freedreno/ir3/ir3_nir_lower_load_barycentric_at_offset.c b/src/freedreno/ir3/ir3_nir_lower_load_barycentric_at_offset.c
index 903bb8ee8b32a49c2e72128a168e0941008368c4..fe5f42dc97b00be39550d7d7333ba71b9ee91412 100644 (file)
--- a/src/freedreno/ir3/ir3_nir_lower_load_barycentric_at_offset.c
+++ b/src/freedreno/ir3/ir3_nir_lower_load_barycentric_at_offset.c
@@ -63,6 +63,9 @@ ir3_nir_lower_load_barycentric_at_offset_instr(nir_builder *b,
        nir_ssa_def *foo = nir_fddx(b, sij);
        nir_ssa_def *bar = nir_fddy(b, sij);
 
+       if (b->shader->info.stage == MESA_SHADER_FRAGMENT)
+               b->shader->info.fs.needs_helper_invocations = true;
+
        nir_ssa_def *x, *y, *z, *i, *j;
 
        x = nir_ffma(b, chan(off, 0), chan(foo, 0), chan(sij, 0));