diff --git a/src/amd/compiler/aco_lower_phis.cpp b/src/amd/compiler/aco_lower_phis.cpp
index cd314b31c3b..6b8f611ecc7 100644
--- a/src/amd/compiler/aco_lower_phis.cpp
+++ b/src/amd/compiler/aco_lower_phis.cpp
@@ -36,6 +36,7 @@ enum class pred_defined : uint8_t {
    const_1 = 1,
    const_0 = 2,
    temp = 3,
+   zero = 4, /* all disabled lanes are zero'd out */
 };
 MESA_DEFINE_CPP_ENUM_BITFIELD_OPERATORS(pred_defined);
 
@@ -71,7 +72,8 @@ get_ssa(Program* program, unsigned block_idx, ssa_state* state, bool input)
    size_t pred = block.linear_preds.size();
    Operand op;
    if (block.loop_nest_depth < state->loop_nest_depth) {
-      op = Operand(program->lane_mask);
+      /* loop-carried value for loop exit phis */
+      op = Operand::zero(program->lane_mask.bytes());
    } else if (block.loop_nest_depth > state->loop_nest_depth || pred == 1 ||
               block.kind & block_kind_loop_exit) {
       op = get_ssa(program, block.linear_preds[0], state, false);
@@ -160,6 +162,22 @@ build_merge_code(Program* program, ssa_state* state, Block* block, Operand cur)
    }
 
    assert(prev.isTemp());
+   /* simpler sequence in case prev has only zeros in disabled lanes */
+   if ((defined & pred_defined::zero) == pred_defined::zero) {
+      if (cur.isConstant()) {
+         if (!cur.constantValue()) {
+            bld.copy(dst, prev);
+            return;
+         }
+         cur = Operand(exec, bld.lm);
+      } else {
+         cur =
+            bld.sop2(Builder::s_and, bld.def(bld.lm), bld.def(s1, scc), cur, Operand(exec, bld.lm));
+      }
+      bld.sop2(Builder::s_or, dst, bld.def(s1, scc), prev, cur);
+      return;
+   }
+
    if (cur.isConstant()) {
       if (cur.constantValue())
          bld.sop2(Builder::s_or, dst, bld.def(s1, scc), prev, Operand(exec, bld.lm));
@@ -208,6 +226,18 @@ init_any_pred_defined(Program* program, ssa_state* state, Block* block, aco_ptr<
       state->any_pred_defined[block->index] = pred_defined::undef;
    }
 
+   /* add dominating zero: this allows to emit simpler merge sequences
+    * if we can ensure that all disabled lanes are always zero on incoming values */
+   // TODO: find more occasions where pred_defined::zero is beneficial (e.g. with 2+ temp merges)
+   if (block->kind & block_kind_loop_exit) {
+      /* zero the loop-carried variable */
+      if (program->blocks[start].linear_preds.size() > 1) {
+         state->any_pred_defined[start] |= pred_defined::zero;
+         // TODO: emit this zero explicitly
+         state->any_pred_defined[start - 1] = pred_defined::const_0;
+      }
+   }
+
    for (unsigned j = start; j < end; j++) {
       if (state->any_pred_defined[j] == pred_defined::undef)
          continue;