add a unit test for a problematic optimization pattern to prevent it …

…from happening again
santiontanon · Sep 6, 2022 · fa20fb1 · fa20fb1
1 parent 4ad6514
commit fa20fb1
Show file tree

Hide file tree

Showing 4 changed files with 28 additions and 7 deletions.
diff --git a/src/main/java/workers/pattopt/Pattern.java b/src/main/java/workers/pattopt/Pattern.java
@@ -270,12 +270,16 @@ public int getSpaceSaving(PatternMatch match, CodeBase code)
         for(CPUOpPattern pat:replacement) {
             if (!pat.isWildcard()) {
                 CPUOp ipat = pat.instantiate(match, this, config);
-                int irepSize = ipat.sizeInBytes();
-                int n = 1;
-                if (pat.repetitionVariable != null) {
-                    n = match.variables.get(pat.repetitionVariable).evaluateToInteger(null, code, true);
+                if (ipat == null) {
+                    config.error("An optimization pattern ("+this.name+") has generated ilegal code!");
+                } else {
+                    int irepSize = ipat.sizeInBytes();
+                    int n = 1;
+                    if (pat.repetitionVariable != null) {
+                        n = match.variables.get(pat.repetitionVariable).evaluateToInteger(null, code, true);
+                    }
+                    replacementSize += n * irepSize;
                 }
-                replacementSize += n * irepSize;
             }
         }
         int spaceSaving = patternSize - replacementSize;
@@ -289,7 +293,12 @@ public int[] getTimeSaving(PatternMatch match, CodeBase code)
         int replacementTime[] = {0,0};
         for(CPUOpPattern pat:pattern) {
             if (!pat.isWildcard()) {
-                int tmp[] = pat.instantiate(match, this, config).timing();
+                CPUOp ipat = pat.instantiate(match, this, config);
+                if (ipat == null) {
+                    config.error("An optimization pattern ("+this.name+") has generated ilegal code!");
+                    continue;
+                } 
+                int tmp[] = ipat.timing();
                 int n = 1;
                 if (pat.repetitionVariable != null) {
                     n = match.variables.get(pat.repetitionVariable).evaluateToInteger(null, code, true);
@@ -304,7 +313,12 @@ public int[] getTimeSaving(PatternMatch match, CodeBase code)
         }
         for(CPUOpPattern pat:replacement) {
             if (!pat.isWildcard()) {
-                int tmp[] = pat.instantiate(match, this, config).timing();
+                CPUOp ipat = pat.instantiate(match, this, config);
+                if (ipat == null) {
+                    config.error("An optimization pattern ("+this.name+") has generated ilegal code!");
+                    continue;
+                } 
+                int tmp[] = ipat.timing();
                 int n = 1;
                 if (pat.repetitionVariable != null) {
                     n = match.variables.get(pat.repetitionVariable).evaluateToInteger(null, code, true);

diff --git a/src/main/resources/data/pbo-patterns.txt b/src/main/resources/data/pbo-patterns.txt
@@ -84,6 +84,7 @@ pattern: Remove unused ld ?reg,?any
 0: ld ?reg,?any
 replacement:
 constraints:
+notIn(?reg,I)
 regsNotUsedAfter(0,?reg)
 
 pattern: Replace ld a,?const with xor a
@@ -1928,6 +1929,7 @@ replacement:
 1: *
 2: ld ?reg2,?const1
 constraints:
+notIn(?reg2,I)
 regsNotUsed(1,?reg1)
 regsNotUsedAfter(2,?reg1)
 

diff --git a/src/test/java/test/PatternBasedOptimizerTest.java b/src/test/java/test/PatternBasedOptimizerTest.java
@@ -112,6 +112,7 @@ public PatternBasedOptimizerTest() {
     @Test public void test73() throws Exception { test("data/potests/test73.asm", null, null, "speed", 10, 74, 74, "data/potests/test73-expected.asm"); }
     @Test public void test74() throws Exception { test("data/potests/test74.asm", null, null, "speed", 3, 28, 28, "data/potests/test74-expected.asm"); }
     @Test public void test75() throws Exception { test("data/potests/test75.asm", "sdcc", null, "speed", 1, 3, 3, "data/potests/test75-expected.asm"); }
+    @Test public void test76() throws Exception { test("data/potests/test76.asm", null, null, "size", 0, 0, 0, null); }
 
 
     private void test(String inputFile, String dialect, String cpu, String target,

diff --git a/src/test/resources/data/potests/test76.asm b/src/test/resources/data/potests/test76.asm
@@ -0,0 +1,4 @@
+org #4000
+
+  ld a, #fe
+  ld i, a