From: Kenneth Graunke <kenneth@whitecape.org>
Date: Mon, 30 Mar 2015 23:09:51 +0000 (-0700)
Subject: nir: Use _mesa_flsll(InputsRead) in prog->nir.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=25e214db0094306835a03225e1a37164c7c98bf7;p=mesa.git

nir: Use _mesa_flsll(InputsRead) in prog->nir.

InputsRead is a 64-bit bitfield.  Using _mesa_fls would silently
truncate off the high bits, claiming inputs 32..56 (VARYING_SLOT_MAX)
were never read.

Using <= here was a hack I threw in at the last minute to fix programs
which happened to use input slot 32.  Switch back to using < now that
the underlying problem is fixed.

Fixes crashes in "Euro Truck Simulator 2" when using prog->nir, which
uses input slot 33.

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
---

diff --git a/src/mesa/program/prog_to_nir.c b/src/mesa/program/prog_to_nir.c
index 4e210d190de..5f00a8b2fd0 100644
--- a/src/mesa/program/prog_to_nir.c
+++ b/src/mesa/program/prog_to_nir.c
@@ -931,8 +931,8 @@ setup_registers_and_variables(struct ptn_compile *c)
    struct nir_shader *shader = b->shader;
 
    /* Create input variables. */
-   const int last_input = _mesa_fls(c->prog->InputsRead);
-   for (int i = 0; i <= last_input; i++) {
+   const int num_inputs = _mesa_flsll(c->prog->InputsRead);
+   for (int i = 0; i < num_inputs; i++) {
       if (!(c->prog->InputsRead & BITFIELD64_BIT(i)))
          continue;
       nir_variable *var = rzalloc(shader, nir_variable);