From 08f486203b026461d56386ce069ea5df1f47dc52 Mon Sep 17 00:00:00 2001
From: Marvin Kaiser <marvin.kaiser.93@gmail.com>
Date: Tue, 17 Dec 2019 17:22:44 +0100
Subject: [PATCH] Fix: Arguments that don't fit into registeres are passed in
 the incorrect order

---
 .../de/hsrm/compiler/Klang/visitors/GenASM.java | 17 +++++++++--------
 src/test/functionCall/functionCall.c            |  2 +-
 src/test/testCode.c                             |  2 +-
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/src/main/java/de/hsrm/compiler/Klang/visitors/GenASM.java b/src/main/java/de/hsrm/compiler/Klang/visitors/GenASM.java
index a0fbcd2..fcb2597 100644
--- a/src/main/java/de/hsrm/compiler/Klang/visitors/GenASM.java
+++ b/src/main/java/de/hsrm/compiler/Klang/visitors/GenASM.java
@@ -222,20 +222,21 @@ public class GenASM implements Visitor<Void> {
     this.env = new HashMap<String, Integer>();
 
     // Merke dir die offsets der parameter, die direkt auf den stack gelegt wurden
-    int m = e.parameters.length - this.rs.length;
-    for (int i = this.rs.length; i < e.parameters.length; i++) {
-      int j = i - this.rs.length;
-      this.env.put(e.parameters[i], (((m - j) + 1) * 8)); // positiv, liegt über unserem stack frame
-    }
+    int offset = 16; // Per Stack übergebene Parameter liegen über unserm BSP
+    // Per stack übergebene variablen in env registrieren
+		for (int i = this.rs.length; i < e.parameters.length; i++) {
+			env.put(e.parameters[i], offset);
+			offset += 8;
+		}
 
     // pushe die aufrufparameter aus den Registern wieder auf den Stack
-    int offset = 0;
+    offset = 0;
     for (int i = 0; i < Math.min(this.rs.length, e.parameters.length); i++) {
       this.ex.write("    pushq " + this.rs[i] + "\n");
       offset -= 8;
       this.env.put(e.parameters[i], offset); // negative, liegt unter aktuellem BP
     }
-
+    
     // Reserviere Platz auf dem Stack für jede lokale variable
     for (String lok_var : vars) {
       offset -= 8;
@@ -256,7 +257,7 @@ public class GenASM implements Visitor<Void> {
     }
 
     // Den Rest auf den stack pushen
-    for (int i = this.rs.length; i < e.arguments.length; i++) {
+    for (int i = e.arguments.length -1; i >= this.rs.length; i--) {
       e.arguments[i].welcome(this);
       this.ex.write("  pushq %rax\n");
     }
diff --git a/src/test/functionCall/functionCall.c b/src/test/functionCall/functionCall.c
index fc30112..b097e95 100644
--- a/src/test/functionCall/functionCall.c
+++ b/src/test/functionCall/functionCall.c
@@ -21,7 +21,7 @@ int argumentTest(char* name, int expected, int result) {
 
 int runFunctionCallTests () {
   int failed = 0;
-  printf("\nFunctionCallTests Tests \n");
+  printf("\nFunction Call Tests \n");
   // Checks that parameters are correctly passed from gcc to functions
   failed += argumentTest("arg1", 1, arg1(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
   failed += argumentTest("arg2", 2, arg2(1, 2, 3, 4, 5, 6, 7, 8, 9, 10));
diff --git a/src/test/testCode.c b/src/test/testCode.c
index 865c775..609306f 100644
--- a/src/test/testCode.c
+++ b/src/test/testCode.c
@@ -105,7 +105,7 @@ int main(){
   failed +=  testOneArg("id", cId, id, -1);
   failed +=  testOneArg("id", cId, id, 15);
 
-  printf("\nFunction Argument Tests\n");
+  // Test for passing arguments to functions
   failed += runFunctionCallTests();
 
   printf("\n=== Failed Tests: %d\n", failed);