From: Marek Olšák <marek.olsak@amd.com>
Date: Fri, 15 Jan 2016 20:58:53 +0000 (+0100)
Subject: radeonsi: disable SPI color outputs the shader doesn't write
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=99dfeb01bd5c3e059968e934f3ec88b2fe43e3f4;p=mesa.git

radeonsi: disable SPI color outputs the shader doesn't write

Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
---

diff --git a/src/gallium/drivers/radeonsi/si_shader.h b/src/gallium/drivers/radeonsi/si_shader.h
index f49290afadf..50375e28ea4 100644
--- a/src/gallium/drivers/radeonsi/si_shader.h
+++ b/src/gallium/drivers/radeonsi/si_shader.h
@@ -213,6 +213,10 @@ struct si_shader_selector {
 
 	/* PS parameters. */
 	unsigned	db_shader_control;
+	/* Set 0xf or 0x0 (4 bits) per each written output.
+	 * ANDed with spi_shader_col_format.
+	 */
+	unsigned	colors_written_4bit;
 
 	/* masks of "get_unique_index" bits */
 	uint64_t	outputs_written;
diff --git a/src/gallium/drivers/radeonsi/si_state_shaders.c b/src/gallium/drivers/radeonsi/si_state_shaders.c
index 59aee54c3b1..79f2335b9b5 100644
--- a/src/gallium/drivers/radeonsi/si_state_shaders.c
+++ b/src/gallium/drivers/radeonsi/si_state_shaders.c
@@ -647,6 +647,12 @@ static inline void si_shader_selector_key(struct pipe_context *ctx,
 		if (sctx->b.chip_class <= CIK && sctx->b.family != CHIP_HAWAII)
 			key->ps.color_is_int8 = sctx->framebuffer.color_is_int8;
 
+		/* Disable unwritten outputs (if WRITE_ALL_CBUFS isn't enabled). */
+		if (!key->ps.last_cbuf) {
+			key->ps.spi_shader_col_format &= sel->colors_written_4bit;
+			key->ps.color_is_int8 &= sel->info.colors_written;
+		}
+
 		if (rs) {
 			bool is_poly = (sctx->current_rast_prim >= PIPE_PRIM_TRIANGLES &&
 					sctx->current_rast_prim <= PIPE_PRIM_POLYGON) ||
@@ -831,6 +837,12 @@ static void *si_create_shader_selector(struct pipe_context *ctx,
 		}
 		sel->esgs_itemsize = util_last_bit64(sel->outputs_written) * 16;
 		break;
+
+	case PIPE_SHADER_FRAGMENT:
+		for (i = 0; i < 8; i++)
+			if (sel->info.colors_written & (1 << i))
+				sel->colors_written_4bit |= 0xf << (4 * i);
+		break;
 	}
 
 	/* DB_SHADER_CONTROL */