1 files changed, 122 insertions, 0 deletions
diff --git a/libinterp/decgen.c b/libinterp/decgen.c
new file mode 100644
index 00000000..f81749c7
--- /dev/null
+++ b/libinterp/decgen.c
@@ -0,0 +1,122 @@
+#include "lib9.h"
+#include "isa.h"
+#include "interp.h"
+
+void	decgen(int);
+
+/*
+ * Force intermediate dereference of $o(o(reg)) modes to ensure intermediate
+ * pointer is valid. This is required if you want secure memory.
+ */
+#define	SOFTMMU		0
+
+void
+main(void)
+{
+	int i;
+
+	print("/* Machine generated by decgen.c */\n\n");
+
+	print("#include \"lib9.h\"\n");
+	print("#include \"isa.h\"\n");
+	print("#include \"interp.h\"\n\n");
+
+	print("#define DIND(reg, xxx) (uchar*)((*(ulong*)(R.reg+R.PC->xxx.i.f))+R.PC->xxx.i.s)\n");
+
+	for(i = 0; i < 256; i++)
+		decgen(i);
+
+	print("\nvoid	(*dec[])(void) =\n{\n");
+	for(i = 0; i < 256; i++)
+		print("\tD%.2uX%c\n", i, i != 255 ? ',' : ' ');
+	print("};\n");
+}
+
+void
+decgen(int addr)
+{
+	int nodst;
+
+	print("static void\nD%.2uX(void)\n{\n", addr);
+
+	switch(USRC(addr)) {
+	case AMP:
+		print("\tR.s = R.MP+R.PC->s.ind;\n");
+		break;
+	case AFP:
+		print("\tR.s = R.FP+R.PC->s.ind;\n");
+		break;
+	case AIMM:
+		print("\tR.s = (uchar*)&R.PC->s.imm;\n");
+		break;
+	case AMP|AIND:
+		if(SOFTMMU) {
+			print("R.s = R.MP+R.PC->s.i.f\n");
+			print("R.s = *(WORD**)R.s\n");
+			print("R.s = (uchar*)R.s + R.PC->s.i.s\n");
+		}
+		else
+			print("\tR.s = DIND(MP, s);\n");
+		break;
+	case AFP|AIND:
+		if(SOFTMMU) {
+			print("R.s = R.FP+R.PC->s.i.f\n");
+			print("R.s = *(WORD**)R.s\n");
+			print("R.s = (uchar*)R.s + R.PC->s.i.s\n");
+		}
+		else
+			print("\tR.s = DIND(FP, s);\n");
+		break;
+	}
+	nodst = 0;
+	switch(UDST(addr)) {
+	default:
+		nodst = 1;
+		break;
+	case AMP:
+		print("\tR.d = R.MP+R.PC->d.ind;\n");
+		break;
+	case AFP:
+		print("\tR.d = R.FP+R.PC->d.ind;\n");
+		break;
+	case AIMM:
+		print("\tR.d = (uchar*)&R.PC->d.imm;\n");
+		break;
+	case AMP|AIND:
+		if(SOFTMMU) {
+			print("R.d = R.MP+R.PC->d.i.f\n");
+			print("R.d = *(WORD**)R.d\n");
+			print("R.d = (uchar*)R.d + R.PC->d.i.s\n");
+		}
+		else
+			print("\tR.d = DIND(MP, d);\n");
+		break;
+	case AFP|AIND:
+		if(SOFTMMU) {
+			print("R.d = R.FP+R.PC->d.i.f\n");
+			print("R.d = *(WORD**)R.d\n");
+			print("R.d = (uchar*)R.d + R.PC->d.i.s\n");
+		}
+		else
+			print("\tR.d = DIND(FP, d);\n");
+		break;
+	}
+
+	if(nodst == 0)
+	switch(addr&ARM) {
+	case AXNON:
+		print("\tR.m = R.d;\n");
+		break;
+	case AXIMM:
+		print("\tR.t = (short)R.PC->reg;\n");
+		print("\tR.m = &R.t;\n");
+		break;
+	case AXINF:
+		print("\tR.m = R.FP+R.PC->reg;\n");
+		break;
+	case AXINM:
+		print("\tR.m = R.MP+R.PC->reg;\n");
+		break;
+	}
+	print("}\n");
+}