freedreno/ir3: Track whether shader needs derivatives

In 1088b788 ("freedreno/ir3: find # of samplers from uniform vars") we
started counting number of samplers based on the uniform vars instead
of number of cat5 instructions.  We used the number of samplers to
determine whether to enable derivatives, but when we only use
derivatives and no samplers, that now breaks.  Track whether we need
derivatives explicitly and use that to enable the state.

Fixes: 1088b788 ("freedreno/ir3: find # of samplers from uniform vars")
Signed-off-by: Kristian H. Kristensen <hoegsberg@chromium.org>
Reviewed-by: Rob Clark <robdclark@gmail.com>

6 files changed, 12 insertions, 6 deletions

diff --git a/src/freedreno/ir3/ir3.h b/src/freedreno/ir3/ir3.h
index 245320fe2fdc..6e30f74d4ab6 100644
--- a/src/freedreno/ir3/ir3.h
+++ b/src/freedreno/ir3/ir3.h
@@ -1028,7 +1028,7 @@ int ir3_ra(struct ir3 *ir3, gl_shader_stage type,
 		bool frag_coord, bool frag_face);
 
 /* legalize: */
-void ir3_legalize(struct ir3 *ir, bool *has_ssbo, int *max_bary);
+void ir3_legalize(struct ir3 *ir, bool *has_ssbo, bool *need_pixlod, int *max_bary);
 
 /* ************************************************************************* */
 /* instruction helpers */
diff --git a/src/freedreno/ir3/ir3_compiler_nir.c b/src/freedreno/ir3/ir3_compiler_nir.c
index 402da13792bd..57a8758140b2 100644
--- a/src/freedreno/ir3/ir3_compiler_nir.c
+++ b/src/freedreno/ir3/ir3_compiler_nir.c
@@ -2798,7 +2798,7 @@ ir3_compile_shader_nir(struct ir3_compiler *compiler,
 	/* We need to do legalize after (for frag shader's) the "bary.f"
 	 * offsets (inloc) have been assigned.
 	 */
-	ir3_legalize(ir, &so->has_ssbo, &max_bary);
+	ir3_legalize(ir, &so->has_ssbo, &so->need_pixlod, &max_bary);
 
 	if (ir3_shader_debug & IR3_DBG_OPTMSGS) {
 		printf("AFTER LEGALIZE:\n");
diff --git a/src/freedreno/ir3/ir3_legalize.c b/src/freedreno/ir3/ir3_legalize.c
index f015c6fede88..cb9a3f972923 100644
--- a/src/freedreno/ir3/ir3_legalize.c
+++ b/src/freedreno/ir3/ir3_legalize.c
@@ -42,6 +42,7 @@
 struct ir3_legalize_ctx {
 	struct ir3_compiler *compiler;
 	bool has_ssbo;
+	bool need_pixlod;
 	int max_bary;
 };
 
@@ -218,6 +219,7 @@ legalize_block(struct ir3_legalize_ctx *ctx, struct ir3_block *block)
 
 		if (is_tex(n)) {
 			regmask_set(&state->needs_sy, n->regs[0]);
+			ctx->need_pixlod = true;
 		} else if (n->opc == OPC_RESINFO) {
 			regmask_set(&state->needs_ss, n->regs[0]);
 			ir3_NOP(block)->flags |= IR3_INSTR_SS;
@@ -471,7 +473,7 @@ mark_convergence_points(struct ir3 *ir)
 }
 
 void
-ir3_legalize(struct ir3 *ir, bool *has_ssbo, int *max_bary)
+ir3_legalize(struct ir3 *ir, bool *has_ssbo, bool *need_pixlod, int *max_bary)
 {
 	struct ir3_legalize_ctx *ctx = rzalloc(ir, struct ir3_legalize_ctx);
 	bool progress;
@@ -493,6 +495,7 @@ ir3_legalize(struct ir3 *ir, bool *has_ssbo, int *max_bary)
 	} while (progress);
 
 	*has_ssbo = ctx->has_ssbo;
+	*need_pixlod = ctx->need_pixlod;
 	*max_bary = ctx->max_bary;
 
 	do {
diff --git a/src/freedreno/ir3/ir3_shader.h b/src/freedreno/ir3/ir3_shader.h
index d598dd76eee8..647651c03b0c 100644
--- a/src/freedreno/ir3/ir3_shader.h
+++ b/src/freedreno/ir3/ir3_shader.h
@@ -431,6 +431,9 @@ struct ir3_shader_variant {
 	/* do we have one or more SSBO instructions: */
 	bool has_ssbo;
 
+	/* do we need derivatives: */
+	bool need_pixlod;
+
 	/* do we have kill, image write, etc (which prevents early-z): */
 	bool no_earlyz;
 
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_compute.c b/src/gallium/drivers/freedreno/a6xx/fd6_compute.c
index 1219d7ad9b36..f3bc0ed231d5 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_compute.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_compute.c
@@ -96,7 +96,7 @@ cs_program_emit(struct fd_ringbuffer *ring, struct ir3_shader_variant *v,
 			A6XX_SP_CS_CTRL_REG0_FULLREGFOOTPRINT(i->max_reg + 1) |
 			A6XX_SP_CS_CTRL_REG0_MERGEDREGS |
 			A6XX_SP_CS_CTRL_REG0_BRANCHSTACK(v->branchstack) |
-			COND(v->num_samp > 0, A6XX_SP_CS_CTRL_REG0_PIXLODENABLE));
+			COND(v->need_pixlod, A6XX_SP_CS_CTRL_REG0_PIXLODENABLE));
 
 	OUT_PKT4(ring, REG_A6XX_SP_CS_UNKNOWN_A9B1, 1);
 	OUT_RING(ring, 0x41);
diff --git a/src/gallium/drivers/freedreno/a6xx/fd6_program.c b/src/gallium/drivers/freedreno/a6xx/fd6_program.c
index 668b10cccc94..c20472f63c26 100644
--- a/src/gallium/drivers/freedreno/a6xx/fd6_program.c
+++ b/src/gallium/drivers/freedreno/a6xx/fd6_program.c
@@ -396,7 +396,7 @@ setup_stateobj(struct fd_ringbuffer *ring,
 			A6XX_SP_VS_CTRL_REG0_FULLREGFOOTPRINT(s[VS].i->max_reg + 1) |
 			A6XX_SP_VS_CTRL_REG0_MERGEDREGS |
 			A6XX_SP_VS_CTRL_REG0_BRANCHSTACK(s[VS].v->branchstack) |
-			COND(s[VS].v->num_samp > 0, A6XX_SP_VS_CTRL_REG0_PIXLODENABLE));
+			COND(s[VS].v->need_pixlod, A6XX_SP_VS_CTRL_REG0_PIXLODENABLE));
 
 	struct ir3_shader_linkage l = {0};
 	ir3_link_shaders(&l, s[VS].v, s[FS].v);
@@ -518,7 +518,7 @@ setup_stateobj(struct fd_ringbuffer *ring,
 			A6XX_SP_FS_CTRL_REG0_FULLREGFOOTPRINT(s[FS].i->max_reg + 1) |
 			A6XX_SP_FS_CTRL_REG0_MERGEDREGS |
 			A6XX_SP_FS_CTRL_REG0_BRANCHSTACK(s[FS].v->branchstack) |
-			COND(s[FS].v->num_samp > 0, A6XX_SP_FS_CTRL_REG0_PIXLODENABLE));
+			COND(s[FS].v->need_pixlod, A6XX_SP_FS_CTRL_REG0_PIXLODENABLE));
 
 	OUT_PKT4(ring, REG_A6XX_SP_UNKNOWN_A982, 1);
 	OUT_RING(ring, 0);        /* XXX */