nouveau: Use bitmask/ffs to iterate enabled lights

Replaces a loop that iterates all lights and test
which of them is enabled by a loop only iterating over
the bits set in the enabled bitmask.

v2: Use _mesa_bit_scan{,64} instead of open coding.
v3: Use u_bit_scan{,64} instead of _mesa_bit_scan{,64}.

Reviewed-by: Brian Paul <[email protected]>
Signed-off-by: Mathias Fröhlich <[email protected]>

3 files changed, 38 insertions, 26 deletions

diff --git a/src/mesa/drivers/dri/nouveau/nouveau_state.c b/src/mesa/drivers/dri/nouveau/nouveau_state.c
index 3aad10ed62e..6189997397f 100644
--- a/src/mesa/drivers/dri/nouveau/nouveau_state.c
+++ b/src/mesa/drivers/dri/nouveau/nouveau_state.c
@@ -31,6 +31,7 @@
 
 #include "swrast/swrast.h"
 #include "tnl/tnl.h"
+#include "util/bitscan.h"
 
 static void
 nouveau_alpha_func(struct gl_context *ctx, GLenum func, GLfloat ref)
@@ -122,7 +123,7 @@ nouveau_draw_buffers(struct gl_context *ctx, GLsizei n, const GLenum *buffers)
 static void
 nouveau_enable(struct gl_context *ctx, GLenum cap, GLboolean state)
 {
-	int i;
+	GLbitfield mask;
 
 	switch (cap) {
 	case GL_ALPHA_TEST:
@@ -187,9 +188,10 @@ nouveau_enable(struct gl_context *ctx, GLenum cap, GLboolean state)
 		context_dirty(ctx, LIGHT_MODEL);
 		context_dirty(ctx, LIGHT_ENABLE);
 
-		for (i = 0; i < MAX_LIGHTS; i++) {
-			if (ctx->Light.Light[i].Enabled)
-				context_dirty_i(ctx, LIGHT_SOURCE, i);
+		mask = ctx->Light._EnabledLights;
+		while (mask) {
+			const int i = u_bit_scan(&mask);
+			context_dirty_i(ctx, LIGHT_SOURCE, i);
 		}
 
 		context_dirty(ctx, MATERIAL_FRONT_AMBIENT);
diff --git a/src/mesa/drivers/dri/nouveau/nv10_state_tnl.c b/src/mesa/drivers/dri/nouveau/nv10_state_tnl.c
index 1398385b262..9f80e413577 100644
--- a/src/mesa/drivers/dri/nouveau/nv10_state_tnl.c
+++ b/src/mesa/drivers/dri/nouveau/nv10_state_tnl.c
@@ -30,8 +30,7 @@
 #include "nouveau_util.h"
 #include "nv10_3d.xml.h"
 #include "nv10_driver.h"
-
-#include "util/simple_list.h"
+#include "util/bitscan.h"
 
 void
 nv10_emit_clip_plane(struct gl_context *ctx, int emit)
@@ -323,7 +322,7 @@ nv10_emit_material_ambient(struct gl_context *ctx, int emit)
 	struct nouveau_pushbuf *push = context_push(ctx);
 	float (*mat)[4] = ctx->Light.Material.Attrib;
 	float c_scene[3], c_factor[3];
-	struct gl_light *l;
+	GLbitfield mask;
 
 	if (USE_COLOR_MATERIAL(AMBIENT)) {
 		COPY_3V(c_scene, ctx->Light.Model.Ambient);
@@ -347,8 +346,10 @@ nv10_emit_material_ambient(struct gl_context *ctx, int emit)
 		PUSH_DATAp(push, c_factor, 3);
 	}
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(AMBIENT) ?
 				  l->Ambient :
 				  l->_MatAmbient[0]);
@@ -363,13 +364,15 @@ nv10_emit_material_diffuse(struct gl_context *ctx, int emit)
 {
 	struct nouveau_pushbuf *push = context_push(ctx);
 	GLfloat (*mat)[4] = ctx->Light.Material.Attrib;
-	struct gl_light *l;
+	GLbitfield mask;
 
 	BEGIN_NV04(push, NV10_3D(MATERIAL_FACTOR_A), 1);
 	PUSH_DATAf(push, mat[MAT_ATTRIB_FRONT_DIFFUSE][3]);
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(DIFFUSE) ?
 				  l->Diffuse :
 				  l->_MatDiffuse[0]);
@@ -383,10 +386,12 @@ void
 nv10_emit_material_specular(struct gl_context *ctx, int emit)
 {
 	struct nouveau_pushbuf *push = context_push(ctx);
-	struct gl_light *l;
+	GLbitfield mask;
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(SPECULAR) ?
 				  l->Specular :
 				  l->_MatSpecular[0]);
diff --git a/src/mesa/drivers/dri/nouveau/nv20_state_tnl.c b/src/mesa/drivers/dri/nouveau/nv20_state_tnl.c
index 41395516ea4..607a5c0314a 100644
--- a/src/mesa/drivers/dri/nouveau/nv20_state_tnl.c
+++ b/src/mesa/drivers/dri/nouveau/nv20_state_tnl.c
@@ -31,8 +31,7 @@
 #include "nv20_3d.xml.h"
 #include "nv10_driver.h"
 #include "nv20_driver.h"
-
-#include "util/simple_list.h"
+#include "util/bitscan.h"
 
 #define LIGHT_MODEL_AMBIENT_R(side)			\
 	((side) ? NV20_3D_LIGHT_MODEL_BACK_AMBIENT_R :	\
@@ -240,7 +239,7 @@ nv20_emit_material_ambient(struct gl_context *ctx, int emit)
 	struct nouveau_pushbuf *push = context_push(ctx);
 	float (*mat)[4] = ctx->Light.Material.Attrib;
 	float c_scene[3], c_factor[3];
-	struct gl_light *l;
+	GLbitfield mask;
 
 	if (USE_COLOR_MATERIAL(AMBIENT, side)) {
 		COPY_3V(c_scene, mat[MAT_ATTRIB_EMISSION(side)]);
@@ -264,8 +263,10 @@ nv20_emit_material_ambient(struct gl_context *ctx, int emit)
 		PUSH_DATAp(push, c_factor, 3);
 	}
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(AMBIENT, side) ?
 				  l->Ambient :
 				  l->_MatAmbient[side]);
@@ -281,13 +282,15 @@ nv20_emit_material_diffuse(struct gl_context *ctx, int emit)
 	const int side = emit - NOUVEAU_STATE_MATERIAL_FRONT_DIFFUSE;
 	struct nouveau_pushbuf *push = context_push(ctx);
 	GLfloat (*mat)[4] = ctx->Light.Material.Attrib;
-	struct gl_light *l;
+	GLbitfield mask;
 
 	BEGIN_NV04(push, SUBC_3D(MATERIAL_FACTOR_A(side)), 1);
 	PUSH_DATAf(push, mat[MAT_ATTRIB_DIFFUSE(side)][3]);
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(DIFFUSE, side) ?
 				  l->Diffuse :
 				  l->_MatDiffuse[side]);
@@ -302,10 +305,12 @@ nv20_emit_material_specular(struct gl_context *ctx, int emit)
 {
 	const int side = emit - NOUVEAU_STATE_MATERIAL_FRONT_SPECULAR;
 	struct nouveau_pushbuf *push = context_push(ctx);
-	struct gl_light *l;
+	GLbitfield mask;
 
-	foreach(l, &ctx->Light.EnabledList) {
-		const int i = l - ctx->Light.Light;
+	mask = ctx->Light._EnabledLights;
+	while (mask) {
+		const int i = u_bit_scan(&mask);
+		struct gl_light *l = &ctx->Light.Light[i];
 		float *c_light = (USE_COLOR_MATERIAL(SPECULAR, side) ?
 				  l->Specular :
 				  l->_MatSpecular[side]);