Issue #1132: Passing structs to function pointers

z88dk · Apr 14, 2019 · 1e79ec0 · 1e79ec0
1 parent f80bed2
commit 1e79ec0
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Showing 6 changed files with 95 additions and 47 deletions.
diff --git a/lib/z80rules.1 b/lib/z80rules.1
@@ -516,15 +516,6 @@
 =
 	pop	de
 
-	pop	bc
-	ld	hl,%1	;const
-	add	hl,sp
-	ld	sp,hl
-=
-	ld	hl,%eval(%1 2 +)	;const
-	add	hl,sp
-	ld	sp,hl
-
 	exx
 	ld	hl,%1	;const
 	add	hl,sp
@@ -4056,3 +4047,26 @@
 	ld	de,0
 	ld	a,h
 	or	l
+
+	ld	hl,%1
+	push	hl
+	ld	hl,%2	;const
+	add	hl,sp
+	ex	de,hl
+	pop	bc
+=
+	ld	hl,%eval(%2 2 -)	;const
+	add	hl,sp
+	ex	de,hl
+	ld	bc,%1
+
+	ld	hl,%1	;const
+	add	hl,sp
+	ld	sp,hl
+	ld	hl,%2	;const
+	add	hl,sp
+	ld	sp,hl
+=
+	ld	hl,%eval(65536 %1 %2 + %)	;const
+	add	hl,sp
+	ld	sp,hl
diff --git a/src/sccz80/callfunc.c b/src/sccz80/callfunc.c
@@ -288,27 +288,8 @@ void callfunction(SYMBOL *ptr, Type *fnptr_type)
             if ( function_pointer_call == 0 ||  fnptr_type->kind == KIND_CPTR ) {
                 nargs += push_function_argument(expr, type, functype->flags & SDCCDECL && argnumber <= array_len(functype->parameters));
             } else {
-                // Regular function pointer
-                if (expr == KIND_LONG || expr == KIND_CPTR) {
-                    if ( tmpfiles[argnumber+1] != NULL ) {
-                        swap(); /* MSW -> hl */
-                        swapstk(); /* MSW -> stack, addr -> hl */
-                        zpushde(); /* LSW -> stack, addr = hl */
-                    }
-                    nargs += 4;
-                    last_argument_size = 4;
-                } else if (expr == KIND_DOUBLE) {
-                    dpush_under(KIND_INT);
-                    nargs += 6;
-                    last_argument_size = 6;
-                    mainpop();
-                } else {
-                    if ( tmpfiles[argnumber+1] != NULL ) {
-                        swapstk();
-                    }
-                    nargs += 2;
-                    last_argument_size = 2;
-                }
+                last_argument_size = push_function_argument_fnptr(expr, type, functype->flags & SDCCDECL && argnumber <= array_len(functype->parameters), tmpfiles[argnumber+1] == NULL);
+                nargs += last_argument_size;
             }
         }
         restore_input();

diff --git a/src/sccz80/codegen.c b/src/sccz80/codegen.c
@@ -703,25 +703,45 @@ int push_function_argument(Kind expr, Type *type, int push_sdccchar)
     return 2;
 }
 
-
-
-
-/* Push structure onto stack - address located in hl */
-void push_struct(Type *type)
+/* Push an argument for a function pointer call */
+int push_function_argument_fnptr(Kind expr, Type *type, int push_sdccchar, int is_last_argument)
 {
-    swap();		/* de = stack address */
-    vconst(-type->size);
-    ol("add\thl,sp");
-    ol("ld\tsp,hl");
-    Zsp -= type->size;
-    swap();
-    outfmt("\tld\tbc,%d\n",type->size);
-    ol("ldir");
+    if (expr == KIND_LONG || expr == KIND_CPTR) {
+        if ( !is_last_argument ) {
+            swap(); /* MSW -> hl */
+            swapstk(); /* MSW -> stack, addr -> hl */
+            zpushde(); /* LSW -> stack, addr = hl */
+        }
+        return 4;
+    } else if (expr == KIND_DOUBLE) {
+        dpush_under(KIND_INT);
+        mainpop();
+        return 6;
+    } else if (expr == KIND_STRUCT ) {
+        // 13 bytes
+        swap();    // de = address of struct
+        ol("pop\tbc");	// return address
+        vconst(-type->size);
+        ol("add\thl,sp");
+        ol("ld\tsp,hl");
+        ol("push\tbc");
+        Zsp -= type->size;
+        swap();
+        outfmt("\tld\tbc,%d\n",type->size);
+        ol("ldir");
+        mainpop();
+        return type->size;
+    } 
+    if ( !is_last_argument ) {
+        swapstk();
+    }
+    return 2;
 }
 
+
+
 /* Push the primary floating point register, preserving
         the top value  */
-
 void dpush_under(int val_type)
 {
     if ( val_type == KIND_LONG ) {
@@ -845,7 +865,7 @@ void callstk(Type *type, int n, int isfarptr, int last_argument_size)
         }
         loadargc(n);
         callrts("l_farcall");
-    } else if ( type->flags & FASTCALL && last_argument_size != 6 ) {
+    } else if ( type->flags & FASTCALL && last_argument_size < 6 ) {
          int label = getlabel();		  
          // TOS = address, dehl = parameter
          // More than one argument, TOS = last parameter, hl = function

diff --git a/src/sccz80/codegen.h b/src/sccz80/codegen.h
@@ -136,4 +136,5 @@ extern void zentercritical(void);
 extern void zleavecritical(void);
 extern int zcriticaloffset(void);
 extern int push_function_argument(Kind expr, Type *type, int push_sdccchar);
+extern int push_function_argument_fnptr(Kind expr, Type *type, int push_sdccchar, int is_last_argument);
 
diff --git a/testsuite/Issue_1132_struct_parameter.c b/testsuite/Issue_1132_struct_parameter.c
@@ -1,11 +1,15 @@
 
 
+
 struct test {
     char   c[10];
     int    x;
     int    y;
 };
 
+typedef void *(*fptr)(struct test x);
+
+static fptr fnptr;
 
 void func(struct test x, int y)
 {
@@ -25,3 +29,10 @@ void func_calling(void)
     func(a, 10);
 }
 
+
+void func_fptr(void)
+{
+    struct test a;
+
+    fnptr(a);
+}
diff --git a/testsuite/results/Issue_1132_struct_parameter.opt b/testsuite/results/Issue_1132_struct_parameter.opt
@@ -47,10 +47,29 @@
 	ld	hl,10	;const
 	push	hl
 	call	_func
-	ld	hl,16	;const
+	ld	hl,30	;const
+	add	hl,sp
+	ld	sp,hl
+	ret
+
+
+
+._func_fptr
+	ld	hl,65522	;const
 	add	hl,sp
 	ld	sp,hl
-	ld	hl,14	;const
+	ex	de,hl
+	ld	bc,(_fnptr)
+	ld	hl,65522	;const
+	add	hl,sp
+	ld	sp,hl
+	push	bc
+	ex	de,hl
+	ld	bc,14
+	ldir
+	pop	hl
+	call	l_jphl
+	ld	hl,28	;const
 	add	hl,sp
 	ld	sp,hl
 	ret
@@ -59,13 +78,15 @@
 
 
 	SECTION	bss_compiler
+._fnptr	defs	2
 	SECTION	code_compiler
 
 
 
 	GLOBAL	_func
 	GLOBAL	_func_callee
 	GLOBAL	_func_calling
+	GLOBAL	_func_fptr