From 32d0bae8ec382b5f604d75b2375e75ffec986fa7 Mon Sep 17 00:00:00 2001
From: Rhys Perry <pendingchaos02@gmail.com>
Date: Fri, 10 Sep 2021 18:20:03 +0100
Subject: [PATCH] aco: fix branch definition validation
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Like how they have to be register allocated differently, branch
definitions at merge block predecessors need to be validated differently.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13432>
---
 src/amd/compiler/aco_validate.cpp | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/amd/compiler/aco_validate.cpp b/src/amd/compiler/aco_validate.cpp
index 7df92a5da39..13e1b55f602 100644
--- a/src/amd/compiler/aco_validate.cpp
+++ b/src/amd/compiler/aco_validate.cpp
@@ -1133,7 +1133,8 @@ validate_ra(Program* program)
             }
          }
 
-         err |= validate_instr_defs(program, regs, assignments, loc, instr);
+         if (!instr->isBranch() || block.linear_succs.size() != 1)
+            err |= validate_instr_defs(program, regs, assignments, loc, instr);
 
          if (!is_phi(instr)) {
             for (const Operand& op : instr->operands) {
@@ -1144,6 +1145,13 @@ validate_ra(Program* program)
                      regs[op.physReg().reg_b + j] = 0;
                }
             }
+         } else if (block.linear_preds.size() != 1 ||
+                    program->blocks[block.linear_preds[0]].linear_succs.size() == 1) {
+            for (unsigned pred : block.linear_preds) {
+               aco_ptr<Instruction>& br = program->blocks[pred].instructions.back();
+               assert(br->isBranch());
+               err |= validate_instr_defs(program, regs, assignments, loc, br);
+            }
          }
       }
    }