Undo second SSA transformation and add more tests.

10 files changed, 235 insertions, 8 deletions

diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/for_loop.yul b/test/libyul/yulOptimizerTests/ssaAndBack/for_loop.yul
new file mode 100644
index 00000000..18498e61
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/for_loop.yul
@@ -0,0 +1,36 @@
+{
+    for {
+      let a := mload(0)
+      let b := mload(1)
+    }
+    lt(mload(a),mload(b))
+    {
+       a := mload(b)
+    }
+    {
+        b := mload(a)
+        a := mload(b)
+        a := mload(b)
+        a := mload(b)
+        b := mload(a)
+    }
+}
+// ----
+// ssaAndBack
+// {
+//     for {
+//         let a := mload(0)
+//         let b := mload(1)
+//     }
+//     lt(mload(a), mload(b))
+//     {
+//         a := mload(b)
+//     }
+//     {
+//         let b_3 := mload(a)
+//         pop(mload(b_3))
+//         pop(mload(b_3))
+//         let a_6 := mload(b_3)
+//         b := mload(a_6)
+//     }
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign.yul b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign.yul
new file mode 100644
index 00000000..23c433d1
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign.yul
@@ -0,0 +1,18 @@
+{
+    let a := mload(0)
+    a := mload(1)
+    a := mload(2)
+    a := mload(3)
+    a := mload(4)
+    mstore(a, 0)
+}
+// ----
+// ssaAndBack
+// {
+//     pop(mload(0))
+//     pop(mload(1))
+//     pop(mload(2))
+//     pop(mload(3))
+//     let a_5 := mload(4)
+//     mstore(a_5, 0)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_if.yul b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_if.yul
new file mode 100644
index 00000000..fd5981ef
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_if.yul
@@ -0,0 +1,22 @@
+{
+    let a := mload(0)
+    if mload(1)
+    {
+        a := mload(1)
+        a := mload(2)
+        a := mload(3)
+    }
+    mstore(a, 0)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     if mload(1)
+//     {
+//         pop(mload(1))
+//         pop(mload(2))
+//         a := mload(3)
+//     }
+//     mstore(a, 0)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_if.yul b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_if.yul
new file mode 100644
index 00000000..b0b3efb5
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_if.yul
@@ -0,0 +1,25 @@
+{
+    let a := mload(0)
+    let b := mload(1)
+    if mload(2) {
+        a := mload(b)
+        b := mload(a)
+        a := mload(b)
+        b := mload(a)
+    }
+    mstore(a, b)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     let b := mload(1)
+//     if mload(2)
+//     {
+//         let a_3 := mload(b)
+//         let b_4 := mload(a_3)
+//         a := mload(b_4)
+//         b := mload(a)
+//     }
+//     mstore(a, b)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_switch.yul b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_switch.yul
new file mode 100644
index 00000000..50f56b87
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_multi_var_switch.yul
@@ -0,0 +1,38 @@
+{
+    let a := mload(0)
+    let b := mload(1)
+    switch mload(2)
+    case 0 {
+        a := mload(b)
+        b := mload(a)
+        a := mload(b)
+        b := mload(a)
+    }
+    default {
+        b := mload(a)
+        a := mload(b)
+        b := mload(a)
+        a := mload(b)
+    }
+    mstore(a, b)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     let b := mload(1)
+//     switch mload(2)
+//     case 0 {
+//         let a_3 := mload(b)
+//         let b_4 := mload(a_3)
+//         a := mload(b_4)
+//         b := mload(a)
+//     }
+//     default {
+//         let b_7 := mload(a)
+//         let a_8 := mload(b_7)
+//         b := mload(a_8)
+//         a := mload(b)
+//     }
+//     mstore(a, b)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_switch.yul b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_switch.yul
new file mode 100644
index 00000000..1efbbde7
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/multi_assign_switch.yul
@@ -0,0 +1,32 @@
+{
+    let a := mload(0)
+    switch mload(1)
+    case 0 {
+        a := mload(1)
+        a := mload(2)
+        a := mload(3)
+    }
+    default {
+        a := mload(4)
+        a := mload(5)
+        a := mload(6)
+    }
+    mstore(a, 0)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     switch mload(1)
+//     case 0 {
+//         pop(mload(1))
+//         pop(mload(2))
+//         a := mload(3)
+//     }
+//     default {
+//         pop(mload(4))
+//         pop(mload(5))
+//         a := mload(6)
+//     }
+//     mstore(a, 0)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/simple.yul b/test/libyul/yulOptimizerTests/ssaAndBack/simple.yul
index 23c433d1..912940c5 100644
--- a/test/libyul/yulOptimizerTests/ssaAndBack/simple.yul
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/simple.yul
@@ -1,18 +1,12 @@
 {
     let a := mload(0)
     a := mload(1)
-    a := mload(2)
-    a := mload(3)
-    a := mload(4)
     mstore(a, 0)
 }
 // ----
 // ssaAndBack
 // {
 //     pop(mload(0))
-//     pop(mload(1))
-//     pop(mload(2))
-//     pop(mload(3))
-//     let a_5 := mload(4)
-//     mstore(a_5, 0)
+//     let a_2 := mload(1)
+//     mstore(a_2, 0)
 // }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_if.yul b/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_if.yul
new file mode 100644
index 00000000..5185245c
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_if.yul
@@ -0,0 +1,18 @@
+{
+    let a := mload(0)
+    if mload(1)
+    {
+        a := mload(1)
+    }
+    mstore(a, 0)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     if mload(1)
+//     {
+//         a := mload(1)
+//     }
+//     mstore(a, 0)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_switch.yul b/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_switch.yul
new file mode 100644
index 00000000..e0e53b3f
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/single_assign_switch.yul
@@ -0,0 +1,24 @@
+{
+    let a := mload(0)
+    switch mload(1)
+    case 0 {
+        a := mload(1)
+    }
+    default {
+        a := mload(2)
+    }
+    mstore(a, 0)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     switch mload(1)
+//     case 0 {
+//         a := mload(1)
+//     }
+//     default {
+//         a := mload(2)
+//     }
+//     mstore(a, 0)
+// }
diff --git a/test/libyul/yulOptimizerTests/ssaAndBack/two_vars.yul b/test/libyul/yulOptimizerTests/ssaAndBack/two_vars.yul
new file mode 100644
index 00000000..85325fb9
--- /dev/null
+++ b/test/libyul/yulOptimizerTests/ssaAndBack/two_vars.yul
@@ -0,0 +1,20 @@
+{
+    let a := mload(0)
+    let b := mload(a)
+    a := mload(b)
+    b := mload(a)
+    a := mload(b)
+    b := mload(a)
+    mstore(a, b)
+}
+// ----
+// ssaAndBack
+// {
+//     let a := mload(0)
+//     let b := mload(a)
+//     let a_3 := mload(b)
+//     let b_4 := mload(a_3)
+//     let a_5 := mload(b_4)
+//     let b_6 := mload(a_5)
+//     mstore(a_5, b_6)
+// }