Mesa (master): r300: Zero-initialize register for NV_vertex_program

[Nicolai Hähnle]

Module: Mesa
Branch: master
Commit: 526430ade1d7ec0e1b3743d69e1ee9fb89cbaa2a
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=526430ade1d7ec0e1b3743d69e1ee9fb89cbaa2a

Author: Nicolai Hähnle <nhaehnle at gmail.com>
Date:   Mon Sep 21 12:50:33 2009 +0200

r300: Zero-initialize register for NV_vertex_program

Signed-off-by: Nicolai Hähnle <nhaehnle at gmail.com>

---

 src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c |    1 +
 src/mesa/drivers/dri/r300/r300_vertprog.c          |   31 ++++++++++++++++++++
 2 files changed, 32 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c b/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
index 93a5161..dad27fc 100644
--- a/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
+++ b/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
@@ -89,6 +89,7 @@ static unsigned long t_dst_index(struct r300_vertex_program_code *vp,
 static unsigned long t_src_class(gl_register_file file)
 {
 	switch (file) {
+	case PROGRAM_BUILTIN:
 	case PROGRAM_TEMPORARY:
 		return PVS_SRC_REG_TEMPORARY;
 	case PROGRAM_INPUT:
diff --git a/src/mesa/drivers/dri/r300/r300_vertprog.c b/src/mesa/drivers/dri/r300/r300_vertprog.c
index dd0f27f..0cb7dde 100644
--- a/src/mesa/drivers/dri/r300/r300_vertprog.c
+++ b/src/mesa/drivers/dri/r300/r300_vertprog.c
@@ -203,6 +203,34 @@ static void t_inputs_outputs(struct r300_vertex_program_compiler * c)
 	}
 }
 
+/**
+ * The NV_vertex_program spec mandates that all registers be
+ * initialized to zero. We do this here unconditionally.
+ *
+ * \note We rely on dead-code elimination in the compiler.
+ */
+static void initialize_NV_registers(struct radeon_compiler * compiler)
+{
+	unsigned int reg;
+	struct rc_instruction * inst;
+
+	for(reg = 0; reg < 12; ++reg) {
+		inst = rc_insert_new_instruction(compiler, &compiler->Program.Instructions);
+		inst->I.Opcode = OPCODE_MOV;
+		inst->I.DstReg.File = PROGRAM_TEMPORARY;
+		inst->I.DstReg.Index = reg;
+		inst->I.SrcReg[0].File = PROGRAM_BUILTIN;
+		inst->I.SrcReg[0].Swizzle = SWIZZLE_0000;
+	}
+
+	inst = rc_insert_new_instruction(compiler, &compiler->Program.Instructions);
+	inst->I.Opcode = OPCODE_ARL;
+	inst->I.DstReg.File = PROGRAM_ADDRESS;
+	inst->I.DstReg.Index = 0;
+	inst->I.DstReg.WriteMask = WRITEMASK_X;
+	inst->I.SrcReg[0].File = PROGRAM_BUILTIN;
+	inst->I.SrcReg[0].Swizzle = SWIZZLE_0000;
+}
 
 static struct r300_vertex_program *build_program(GLcontext *ctx,
 						 struct r300_vertex_program_key *wanted_key,
@@ -234,6 +262,9 @@ static struct r300_vertex_program *build_program(GLcontext *ctx,
 
 	rc_mesa_to_rc_program(&compiler.Base, &vp->Base->Base);
 
+	if (mesa_vp->IsNVProgram)
+		initialize_NV_registers(&compiler.Base);
+
 	rc_move_output(&compiler.Base, VERT_RESULT_PSIZ, VERT_RESULT_PSIZ, WRITEMASK_X);
 
 	if (vp->key.WPosAttr != FRAG_ATTRIB_MAX) {