Mesa (master): Revert "nir: bump loop unroll limit to 96."

[Timothy Arceri]

Module: Mesa
Branch: master
Commit: 1fdb21541e78abeb28ba8dcbc747f5d9f199921b
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=1fdb21541e78abeb28ba8dcbc747f5d9f199921b

Author: Timothy Arceri <tarceri at itsqueeze.com>
Date:   Tue Mar  6 14:48:07 2018 +1100

Revert "nir: bump loop unroll limit to 96."

This reverts commit 2d36efdb7f18f061c519dbb93f6058bf161aad33.

This raised limit turns out to harmful for more complex shaders,
it causes excessive spilling in some Bioshock Infinite shaders.

The fps for the ssao demo on radv remains unchanged when reverting
this.

Reviewed-by: Dave Airlie <airlied at redhat.com>
Reviewed-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>

---

 src/compiler/nir/nir_opt_loop_unroll.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/compiler/nir/nir_opt_loop_unroll.c b/src/compiler/nir/nir_opt_loop_unroll.c
index dae5bfc902..79d04f978b 100644
--- a/src/compiler/nir/nir_opt_loop_unroll.c
+++ b/src/compiler/nir/nir_opt_loop_unroll.c
@@ -33,10 +33,8 @@
  * to give about the same results. Around 5 instructions per node.  But some
  * loops that would unroll with GLSL IR fail to unroll if we set this to 25 so
  * we set it to 26.
- * This was bumped to 96 because it unrolled more loops with a positive
- * effect (vulkan ssao demo).
  */
-#define LOOP_UNROLL_LIMIT 96
+#define LOOP_UNROLL_LIMIT 26
 
 /* Prepare this loop for unrolling by first converting to lcssa and then
  * converting the phis from the loops first block and the block that follows