[Mesa-dev] [PATCH 1/2] radeonsi: Better indexing of parameters in the pixel shader.

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

We were previously using the TGSI input index, which can exceed the number of
parameters passed from the vertex shader via the parameter cache. Now we use
a separate index which only counts those parameters.

Prevents piglit regressions with the following fix.

Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 src/gallium/drivers/radeonsi/radeonsi_shader.c |   10 ++++++----
 src/gallium/drivers/radeonsi/radeonsi_shader.h |    1 +
 src/gallium/drivers/radeonsi/si_state_draw.c   |    9 +++++----
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/gallium/drivers/radeonsi/radeonsi_shader.c b/src/gallium/drivers/radeonsi/radeonsi_shader.c
index 57950a7..dbf2fa4 100644
--- a/src/gallium/drivers/radeonsi/radeonsi_shader.c
+++ b/src/gallium/drivers/radeonsi/radeonsi_shader.c
@@ -239,6 +239,7 @@ static void declare_input_fs(
 {
 	const char * intr_name;
 	unsigned chan;
+	struct si_shader *shader = &si_shader_ctx->shader->shader;
 	struct lp_build_context * base =
 				&si_shader_ctx->radeon_bld.soa.bld_base.base;
 	struct gallivm_state * gallivm = base->gallivm;
@@ -255,10 +256,7 @@ static void declare_input_fs(
 	 * register field value
 	 */
 	LLVMValueRef params = use_sgpr(base->gallivm, SGPR_I32, 6);
-
-
-	/* XXX: Is this the input_index? */
-	LLVMValueRef attr_number = lp_build_const_int32(gallivm, input_index);
+	LLVMValueRef attr_number;
 
 	if (decl->Semantic.Name == TGSI_SEMANTIC_POSITION) {
 		for (chan = 0; chan < TGSI_NUM_CHANNELS; chan++) {
@@ -274,6 +272,10 @@ static void declare_input_fs(
 		return;
 	}
 
+	shader->input[input_index].param_offset = shader->ninterp++;
+	attr_number = lp_build_const_int32(gallivm,
+					   shader->input[input_index].param_offset);
+
 	/* XXX: Handle all possible interpolation modes */
 	switch (decl->Interp.Interpolate) {
 	case TGSI_INTERPOLATE_COLOR:
diff --git a/src/gallium/drivers/radeonsi/radeonsi_shader.h b/src/gallium/drivers/radeonsi/radeonsi_shader.h
index aa2888c..6d2b188 100644
--- a/src/gallium/drivers/radeonsi/radeonsi_shader.h
+++ b/src/gallium/drivers/radeonsi/radeonsi_shader.h
@@ -63,6 +63,7 @@ struct si_shader {
 	unsigned		noutput;
 	struct si_shader_io	output[32];
 
+	unsigned		ninterp;
 	bool			uses_kill;
 	bool			fs_write_all;
 	unsigned		nr_cbufs;
diff --git a/src/gallium/drivers/radeonsi/si_state_draw.c b/src/gallium/drivers/radeonsi/si_state_draw.c
index db8f17f..e6a2a58 100644
--- a/src/gallium/drivers/radeonsi/si_state_draw.c
+++ b/src/gallium/drivers/radeonsi/si_state_draw.c
@@ -101,7 +101,6 @@ static void si_pipe_shader_ps(struct pipe_context *ctx, struct si_pipe_shader *s
 	struct si_pm4_state *pm4;
 	unsigned i, exports_ps, num_cout, spi_ps_in_control, db_shader_control;
 	unsigned num_sgprs, num_user_sgprs;
-	int ninterp = 0;
 	boolean have_linear = FALSE, have_centroid = FALSE, have_perspective = FALSE;
 	unsigned fragcoord_interp_mode = 0;
 	unsigned spi_baryc_cntl, spi_ps_input_ena;
@@ -131,7 +130,7 @@ static void si_pipe_shader_ps(struct pipe_context *ctx, struct si_pipe_shader *s
 			}
 			continue;
 		}
-		ninterp++;
+
 		/* XXX: Flat shading hangs the GPU */
 		if (shader->shader.input[i].interpolate == TGSI_INTERPOLATE_CONSTANT ||
 		    (shader->shader.input[i].interpolate == TGSI_INTERPOLATE_COLOR &&
@@ -172,7 +171,7 @@ static void si_pipe_shader_ps(struct pipe_context *ctx, struct si_pipe_shader *s
 		exports_ps = 2;
 	}
 
-	spi_ps_in_control = S_0286D8_NUM_INTERP(ninterp);
+	spi_ps_in_control = S_0286D8_NUM_INTERP(shader->shader.ninterp);
 
 	spi_baryc_cntl = 0;
 	if (have_perspective)
@@ -365,7 +364,9 @@ static void si_update_spi_map(struct r600_context *rctx)
 			tmp |= S_028644_OFFSET(0x20);
 		}
 
-		si_pm4_set_reg(pm4, R_028644_SPI_PS_INPUT_CNTL_0 + i * 4, tmp);
+		si_pm4_set_reg(pm4,
+			       R_028644_SPI_PS_INPUT_CNTL_0 + ps->input[i].param_offset * 4,
+			       tmp);
 	}
 
 	si_pm4_set_state(rctx, spi, pm4);
-- 
1.7.10.4