Mesa (master): aco: don't fix break condition for break+discard to exec

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: a537c9e73f86d8cb3f4a2b48b4143708b146f0fe
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=a537c9e73f86d8cb3f4a2b48b4143708b146f0fe

Author: Rhys Perry <pendingchaos02 at gmail.com>
Date:   Wed Aug 26 11:10:37 2020 +0100

aco: don't fix break condition for break+discard to exec

This would move the old exec mask back into exec. This also fixes the
live_out_exec.

Issue found in dEQP-VK.graphicsfuzz.cosh-return-inf-unused

Signed-off-by: Rhys Perry <pendingchaos02 at gmail.com>
Reviewed-by: Daniel Schürmann <daniel at schuermann.dev>
Cc: 20.2 <mesa-stable>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6212>

---

 src/amd/compiler/aco_insert_exec_mask.cpp | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/src/amd/compiler/aco_insert_exec_mask.cpp b/src/amd/compiler/aco_insert_exec_mask.cpp
index ccdd5c7d2aa..b682ac77efb 100644
--- a/src/amd/compiler/aco_insert_exec_mask.cpp
+++ b/src/amd/compiler/aco_insert_exec_mask.cpp
@@ -929,6 +929,11 @@ void add_branch_code(exec_ctx& ctx, Block* block)
                             has_discard);
    }
 
+   /* For normal breaks, this is the exec mask. For discard+break, it's the
+    * old exec mask before it was zero'd.
+    */
+   Operand break_cond = bld.exec(ctx.info[idx].exec.back().first);
+
    if (block->kind & block_kind_discard) {
 
       assert(block->instructions.back()->format == Format::PSEUDO_BRANCH);
@@ -961,8 +966,7 @@ void add_branch_code(exec_ctx& ctx, Block* block)
       }
       assert(!ctx.handle_wqm || (ctx.info[block->index].exec[0].second & mask_type_wqm) == 0);
 
-      if ((block->kind & (block_kind_break | block_kind_uniform)) == block_kind_break)
-         ctx.info[idx].exec.back().first = cond;
+      break_cond = Operand(cond);
       bld.insert(std::move(branch));
       /* no return here as it can be followed by a divergent break */
    }
@@ -1055,13 +1059,12 @@ void add_branch_code(exec_ctx& ctx, Block* block)
       assert(block->instructions.back()->opcode == aco_opcode::p_branch);
       block->instructions.pop_back();
 
-      Temp current_exec = ctx.info[idx].exec.back().first;
       Temp cond = Temp();
       for (int exec_idx = ctx.info[idx].exec.size() - 2; exec_idx >= 0; exec_idx--) {
          cond = bld.tmp(s1);
          Temp exec_mask = ctx.info[idx].exec[exec_idx].first;
          exec_mask = bld.sop2(Builder::s_andn2, bld.def(bld.lm), bld.scc(Definition(cond)),
-                              exec_mask, bld.exec(current_exec));
+                              exec_mask, break_cond);
          ctx.info[idx].exec[exec_idx].first = exec_mask;
          if (ctx.info[idx].exec[exec_idx].second & mask_type_loop)
             break;