Mesa (master): aco: don't consider a phi trivial if same's register doesn't match the def

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: 824eba2148e56a75d0678011b4f546cabbd5d345
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=824eba2148e56a75d0678011b4f546cabbd5d345

Author: Rhys Perry <pendingchaos02 at gmail.com>
Date:   Fri Jan 22 10:47:19 2021 +0000

aco: don't consider a phi trivial if same's register doesn't match the def

For example:
 s2: %688:s[32-33] = p_linear_phi %3:s[10-11], %688:s[32-33]
would have been considered trivial.

This might happen due to parallelcopies when assigning phi registers.

Signed-off-by: Rhys Perry <pendingchaos02 at gmail.com>
Reviewed-by: Daniel Schürmann <daniel at schuermann.dev>
Fixes: 69b6069dd28 ("aco: refactor try_remove_trivial_phi() in RA")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8645>

---

 src/amd/compiler/aco_register_allocation.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/amd/compiler/aco_register_allocation.cpp b/src/amd/compiler/aco_register_allocation.cpp
index 8b59317c51b..12d8cb354cf 100644
--- a/src/amd/compiler/aco_register_allocation.cpp
+++ b/src/amd/compiler/aco_register_allocation.cpp
@@ -1778,7 +1778,7 @@ void try_remove_trivial_phi(ra_ctx& ctx, Temp temp)
          assert(t == same || op.physReg() == def.physReg());
          continue;
       }
-      if (same != Temp())
+      if (same != Temp() || op.physReg() != def.physReg())
          return;
 
       same = t;