r300: move dead constants pass earlier for vertex shaders

We need to put it before source conflict resolve because we will be
shuffling immediates around, so we can introduce new conflicts (albeit
in general there should be less conflicts instead).

Signed-off-by: Pavel Ondračka <pavel.ondracka@gmail.com>
Reviewed-by: Filip Gawin <filip.gawin@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28630>

src/gallium/drivers/r300/compiler/r3xx_vertprog.c

@@ -801,10 +801,10 @@ void r3xx_compile_vertex_program(struct r300_vertex_program_compiler *c)
 		{"native rewrite",		1, 1,		rc_local_transform,		alu_rewrite},
 		{"unused channels",		1, opt,		rc_mark_unused_channels,	NULL},
 		{"dataflow optimize",		1, opt,		rc_optimize,			NULL},
+		{"dead constants",		1, 1,		rc_remove_unused_constants,	&c->code->constants_remap_table},
 		/* This pass must be done after optimizations. */
 		{"source conflict resolve",	1, 1,		rc_local_transform,		resolve_src_conflicts},
 		{"register allocation",		1, opt,		allocate_temporary_registers,	NULL},
-		{"dead constants",		1, 1,		rc_remove_unused_constants,	&c->code->constants_remap_table},
 		{"lower control flow opcodes",	1, is_r500,	rc_vert_fc,			NULL},
 		{"final code validation",	0, 1,		rc_validate_final_shader,	NULL},
 		{"machine code generation",	0, 1,		translate_vertex_program,	NULL},