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authorCaio Marcelo de Oliveira Filho <[email protected]>2018-03-19 16:34:16 -0700
committerJason Ekstrand <[email protected]>2018-03-21 09:35:57 -0700
commit470056d37b88070b630c1e95c8590c282dff82fd (patch)
treea3b2ab7b9584f79fccdd8a809f38b88dc271696f
parente1f8c23e18e1e34ab04d5f3c084c9cce44d38553 (diff)
nir/dead_cf: rephrase definition of a dead loop node
Reviewed-by: Jason Ekstrand <[email protected]>
-rw-r--r--src/compiler/nir/nir_opt_dead_cf.c15
1 files changed, 7 insertions, 8 deletions
diff --git a/src/compiler/nir/nir_opt_dead_cf.c b/src/compiler/nir/nir_opt_dead_cf.c
index 53c92ecc286..b15dfdd0c91 100644
--- a/src/compiler/nir/nir_opt_dead_cf.c
+++ b/src/compiler/nir/nir_opt_dead_cf.c
@@ -171,20 +171,19 @@ def_not_live_out(nir_ssa_def *def, void *state)
}
/*
- * Test if a loop is dead. A loop is dead if:
+ * Test if a loop is dead. A loop node is dead if:
*
* 1) It has no side effects (i.e. intrinsics which could possibly affect the
* state of the program aside from producing an SSA value, indicated by a lack
* of NIR_INTRINSIC_CAN_ELIMINATE).
*
- * 2) It has no phi nodes after it, since those indicate values inside the
- * loop being used after the loop.
+ * 2) It has no phi instructions after it, since those indicate values inside
+ * the node being used after the node.
*
- * 3) If there are no phi nodes after the loop, then the only way a value
- * defined inside the loop can be used outside the loop is if its definition
- * dominates the block after the loop. If none of the definitions that
- * dominate the loop exit are used outside the loop, then the loop is dead
- * and it can be deleted.
+ * 3) None of the values defined inside the node is used outside the node,
+ * i.e. none of the definitions that dominate the node exit are used outside.
+ *
+ * If those conditions hold, then the node is dead and can be deleted.
*/
static bool