Fix optimization pass not converging. (#2725)

* Fix optimization pass not converging.

* Fix.

* Fix tests.

---------

Co-authored-by: Yong He <yhe@nvidia.com>

5 files changed, 62 insertions, 71 deletions

diff --git a/tests/experimental/liveness/liveness-3.slang.expected b/tests/experimental/liveness/liveness-3.slang.expected
index d4b417082..7719c6bb1 100644
--- a/tests/experimental/liveness/liveness-3.slang.expected
+++ b/tests/experimental/liveness/liveness-3.slang.expected
@@ -55,15 +55,14 @@ int calcThing_0(int offset_0)
         idx_0[0] = 0;
         idx_0[1] = 0;
         idx_0[2] = 0;
-        int _S2 = (k_0 + 7) % 5;
-        bool _S3 = _S2 == 4;
+        bool _S2 = (k_0 + 7) % 5 == 4;
         int k_1 = k_0 + 1;
         int i_0;
         livenessStart_1(i_0, 0);
         i_0 = 0;
-        int _S4;
-        livenessStart_1(_S4, 0);
-        _S4 = _S1;
+        int _S3;
+        livenessStart_1(_S3, 0);
+        _S3 = _S1;
         for(;;)
         {
             if(i_0 < 17)
@@ -76,71 +75,69 @@ int calcThing_0(int offset_0)
             }
             int modRange_0 = i_0 % 3;
             another_0[i_0 & 1] = another_0[i_0 & 1] + modRange_0;
-            int _S5 = i_0 % 3;
-            int _S6;
+            int _S4;
             if(modRange_0 != 0)
             {
-                int _S7 = _S4;
-                livenessEnd_0(_S4, 0);
-                int _S8 = _S7 + 1;
-                livenessStart_1(_S6, 0);
-                _S6 = _S8;
+                int _S5 = _S3;
+                livenessEnd_0(_S3, 0);
+                int _S6 = _S5 + 1;
+                livenessStart_1(_S4, 0);
+                _S4 = _S6;
             }
             else
             {
-                int _S9 = _S4;
-                livenessEnd_0(_S4, 0);
-                livenessStart_1(_S6, 0);
-                _S6 = _S9;
+                int _S7 = _S3;
+                livenessEnd_0(_S3, 0);
+                livenessStart_1(_S4, 0);
+                _S4 = _S7;
             }
-            idx_0[modRange_0] = idx_0[modRange_0] + (_S6 + i_0);
+            idx_0[modRange_0] = idx_0[modRange_0] + (_S4 + i_0);
             i_0 = i_0 + 1;
-            livenessStart_1(_S4, 0);
-            int _S10 = _S6;
-            livenessEnd_0(_S6, 0);
-            _S4 = _S10;
+            livenessStart_1(_S3, 0);
+            int _S8 = _S4;
+            livenessEnd_0(_S4, 0);
+            _S3 = _S8;
         }
         livenessEnd_0(_S1, 0);
         livenessEnd_0(k_0, 0);
-        if(_S3)
+        if(_S2)
         {
-            livenessEnd_0(_S4, 0);
+            livenessEnd_0(_S3, 0);
             livenessEnd_1(idx_0, 0);
             livenessEnd_2(another_0, 0);
             return total_0;
         }
-        int _S11 = idx_0[0] + idx_0[1];
-        int _S12 = idx_0[2];
+        int _S9 = idx_0[0] + idx_0[1];
+        int _S10 = idx_0[2];
         livenessEnd_1(idx_0, 0);
-        int _S13 = _S11 + _S12;
-        int _S14 = total_0;
+        int _S11 = _S9 + _S10;
+        int _S12 = total_0;
         livenessEnd_0(total_0, 0);
-        int total_1 = _S14 + _S13;
+        int total_1 = _S12 + _S11;
         livenessStart_1(k_0, 0);
         k_0 = k_1;
         livenessStart_1(_S1, 0);
-        int _S15 = _S4;
-        livenessEnd_0(_S4, 0);
-        _S1 = _S15;
+        int _S13 = _S3;
+        livenessEnd_0(_S3, 0);
+        _S1 = _S13;
         livenessStart_1(total_0, 0);
         total_0 = total_1;
     }
     livenessEnd_2(another_0, 0);
-    int _S16 = total_0;
+    int _S14 = total_0;
     livenessEnd_0(total_0, 0);
-    return - _S16;
+    return - _S14;
 }
 
-layout(std430, binding = 0) buffer _S17 {
+layout(std430, binding = 0) buffer _S15 {
     int _data[];
 } outputBuffer_0;
 layout(local_size_x = 4, local_size_y = 1, local_size_z = 1) in;
 void main()
 {
     int index_0 = int(gl_GlobalInvocationID.x);
-    uint _S18 = uint(index_0);
-    int _S19 = calcThing_0(index_0);
-    ((outputBuffer_0)._data[(_S18)]) = _S19;
+    int _S16 = calcThing_0(index_0);
+    ((outputBuffer_0)._data[(uint(index_0))]) = _S16;
     return;
 }
 
diff --git a/tests/experimental/liveness/liveness-4.slang.expected b/tests/experimental/liveness/liveness-4.slang.expected
index 483247ecd..d6662c6a3 100644
--- a/tests/experimental/liveness/liveness-4.slang.expected
+++ b/tests/experimental/liveness/liveness-4.slang.expected
@@ -37,8 +37,7 @@ int calcThing_0(int offset_0)
             livenessEnd_0(k_0, 0);
             break;
         }
-        int _S1 = (k_0 + 7) % 5;
-        bool _S2 = _S1 == 4;
+        bool _S1 = (k_0 + 7) % 5 == 4;
         int k_1 = k_0 + 1;
         int i_0;
         livenessStart_1(i_0, 0);
@@ -57,7 +56,7 @@ int calcThing_0(int offset_0)
             i_0 = i_0 + 1;
         }
         livenessEnd_0(k_0, 0);
-        if(_S2)
+        if(_S1)
         {
             livenessEnd_1(another_0, 0);
             return 1;
@@ -69,16 +68,15 @@ int calcThing_0(int offset_0)
     return -2;
 }
 
-layout(std430, binding = 0) buffer _S3 {
+layout(std430, binding = 0) buffer _S2 {
     int _data[];
 } outputBuffer_0;
 layout(local_size_x = 4, local_size_y = 1, local_size_z = 1) in;
 void main()
 {
     int index_0 = int(gl_GlobalInvocationID.x);
-    uint _S4 = uint(index_0);
-    int _S5 = calcThing_0(index_0);
-    ((outputBuffer_0)._data[(_S4)]) = _S5;
+    int _S3 = calcThing_0(index_0);
+    ((outputBuffer_0)._data[(uint(index_0))]) = _S3;
     return;
 }
 
diff --git a/tests/experimental/liveness/liveness-5.slang.expected b/tests/experimental/liveness/liveness-5.slang.expected
index 5e144a095..c2ce1d741 100644
--- a/tests/experimental/liveness/liveness-5.slang.expected
+++ b/tests/experimental/liveness/liveness-5.slang.expected
@@ -40,8 +40,7 @@ int calcThing_0(int offset_0)
             livenessEnd_0(k_0, 0);
             break;
         }
-        int _S1 = (k_0 + 7) % 5;
-        bool _S2 = _S1 == 4;
+        bool _S1 = (k_0 + 7) % 5 == 4;
         int k_1 = k_0 + 1;
         int i_0;
         livenessStart_1(i_0, 0);
@@ -60,10 +59,10 @@ int calcThing_0(int offset_0)
             i_0 = i_0 + 1;
         }
         livenessEnd_0(k_0, 0);
-        int _S3 = total_0;
+        int _S2 = total_0;
         livenessEnd_0(total_0, 0);
-        int total_1 = _S3 + another_0[k_0 & 1];
-        if(_S2)
+        int total_1 = _S2 + another_0[k_0 & 1];
+        if(_S1)
         {
             livenessEnd_1(another_0, 0);
             return 1;
@@ -84,16 +83,15 @@ int calcThing_0(int offset_0)
     return total_0;
 }
 
-layout(std430, binding = 0) buffer _S4 {
+layout(std430, binding = 0) buffer _S3 {
     int _data[];
 } outputBuffer_0;
 layout(local_size_x = 4, local_size_y = 1, local_size_z = 1) in;
 void main()
 {
     int index_0 = int(gl_GlobalInvocationID.x);
-    uint _S5 = uint(index_0);
-    int _S6 = calcThing_0(index_0);
-    ((outputBuffer_0)._data[(_S5)]) = _S6;
+    int _S4 = calcThing_0(index_0);
+    ((outputBuffer_0)._data[(uint(index_0))]) = _S4;
     return;
 }
 
diff --git a/tests/experimental/liveness/liveness-6.slang.expected b/tests/experimental/liveness/liveness-6.slang.expected
index 0d2e997b2..45e94a242 100644
--- a/tests/experimental/liveness/liveness-6.slang.expected
+++ b/tests/experimental/liveness/liveness-6.slang.expected
@@ -45,8 +45,7 @@ int calcThing_0(int offset_0)
         arr_0[0] = 2;
         arr_0[1] = 3;
         int _S1 = k_0 & 1;
-        int _S2 = (k_0 + 7) % 5;
-        bool _S3 = _S2 == 4;
+        bool _S2 = (k_0 + 7) % 5 == 4;
         int k_1 = k_0 + 1;
         int i_0;
         livenessStart_1(i_0, 0);
@@ -66,13 +65,13 @@ int calcThing_0(int offset_0)
             i_0 = i_0 + 1;
         }
         livenessEnd_0(k_0, 0);
-        int _S4 = total_0;
+        int _S3 = total_0;
         livenessEnd_0(total_0, 0);
-        int total_1 = _S4 + another_0[_S1];
-        int _S5 = arr_0[_S1];
+        int total_1 = _S3 + another_0[_S1];
+        int _S4 = arr_0[_S1];
         livenessEnd_1(arr_0, 0);
-        int total_2 = total_1 + _S5;
-        if(_S3)
+        int total_2 = total_1 + _S4;
+        if(_S2)
         {
             livenessEnd_1(another_0, 0);
             return 1;
@@ -93,16 +92,15 @@ int calcThing_0(int offset_0)
     return total_0;
 }
 
-layout(std430, binding = 0) buffer _S6 {
+layout(std430, binding = 0) buffer _S5 {
     int _data[];
 } outputBuffer_0;
 layout(local_size_x = 4, local_size_y = 1, local_size_z = 1) in;
 void main()
 {
     int index_0 = int(gl_GlobalInvocationID.x);
-    uint _S7 = uint(index_0);
-    int _S8 = calcThing_0(index_0);
-    ((outputBuffer_0)._data[(_S7)]) = _S8;
+    int _S6 = calcThing_0(index_0);
+    ((outputBuffer_0)._data[(uint(index_0))]) = _S6;
     return;
 }
 
diff --git a/tests/experimental/liveness/liveness.slang.expected b/tests/experimental/liveness/liveness.slang.expected
index b0017ea9d..46b8f0922 100644
--- a/tests/experimental/liveness/liveness.slang.expected
+++ b/tests/experimental/liveness/liveness.slang.expected
@@ -92,9 +92,9 @@ layout(local_size_x = 4, local_size_y = 1, local_size_z = 1) in;
 void main()
 {
     int index_0 = int(gl_GlobalInvocationID.x);
-    const int  _S10[100] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
-    int _S11 = index_0 & 7;
-    SomeStruct_0 _S12 = makeSomeStruct_0();
+    SomeStruct_0 _S10 = makeSomeStruct_0();
+    const int  _S11[100] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+    int _S12 = index_0 & 7;
     int v_1 = someSlowFunc_0(index_0);
     bool _S13 = (v_1 & 256) != 0;
     int _S14 = v_1 & 3;
@@ -118,7 +118,7 @@ void main()
         livenessStart_2(s_3, 0);
         SomeStruct_0 t_0;
         livenessStart_2(t_0, 0);
-        t_0 = _S12;
+        t_0 = _S10;
         SomeStruct_0 u_0;
         if(_S13)
         {
@@ -127,7 +127,7 @@ void main()
             livenessStart_2(u_0, 0);
             u_0.a_1 = 0;
             u_0.x_0 = 0;
-            u_0.c_0 = _S10;
+            u_0.c_0 = _S11;
         }
         else
         {
@@ -135,14 +135,14 @@ void main()
             livenessStart_2(x_1, 0);
             x_1.a_1 = 0;
             x_1.x_0 = 0;
-            x_1.c_0 = _S10;
+            x_1.c_0 = _S11;
             x_1.x_0 = ((anotherBuffer_0)._data[(uint(_S14))]) + 1;
             SomeStruct_0 _S15 = x_1;
             livenessEnd_2(x_1, 0);
             livenessStart_2(u_0, 0);
             u_0 = _S15;
         }
-        s_3.c_0[_S11] = s_3.c_0[_S11] + 1;
+        s_3.c_0[_S12] = s_3.c_0[_S12] + 1;
         int _S16 = s_3.x_0 + t_0.x_0;
         SomeStruct_0 _S17 = u_0;
         livenessEnd_2(u_0, 0);