From 9e9b643b935d5e02940b2161c67bd47e66de4918 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Wed, 27 Nov 2019 11:51:06 +0100
Subject: [PATCH] Tune the suite.

---
 libyul/optimiser/Suite.cpp                    | 12 +++++++++++
 ...remove_redundant_assignments_in_switch.yul | 20 +++++++++++++++++++
 2 files changed, 32 insertions(+)
 create mode 100644 test/libyul/yulOptimizerTests/fullSuite/remove_redundant_assignments_in_switch.yul

diff --git a/libyul/optimiser/Suite.cpp b/libyul/optimiser/Suite.cpp
index e35146e93..c7177e655 100644
--- a/libyul/optimiser/Suite.cpp
+++ b/libyul/optimiser/Suite.cpp
@@ -184,6 +184,18 @@ void OptimiserSuite::run(
 			}, ast);
 		}
 
+		{
+			// Prune a bit more in SSA
+			suite.runSequence({
+				ExpressionSplitter::name,
+				SSATransform::name,
+				RedundantAssignEliminator::name,
+				UnusedPruner::name,
+				RedundantAssignEliminator::name,
+				UnusedPruner::name,
+			}, ast);
+		}
+
 		{
 			// Turn into SSA again and simplify
 			suite.runSequence({
diff --git a/test/libyul/yulOptimizerTests/fullSuite/remove_redundant_assignments_in_switch.yul b/test/libyul/yulOptimizerTests/fullSuite/remove_redundant_assignments_in_switch.yul
new file mode 100644
index 000000000..fa1364297
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/fullSuite/remove_redundant_assignments_in_switch.yul
@@ -0,0 +1,20 @@
+ {
+    let x := 0
+    switch mload(x)
+    case 0 { x := x }
+    case 1 { x := 1 }
+    default { invalid() }
+    mstore(1, 1)
+}
+// ====
+// step: fullSuite
+// ----
+// {
+//     {
+//         switch mload(0)
+//         case 0 { }
+//         case 1 { }
+//         default { invalid() }
+//         mstore(1, 1)
+//     }
+// }