Whoopsies, I dropped this

Makefile

@@ -9,7 +9,7 @@ PREFIX = /usr/local
 
 ntc: $(SOURCES) $(HEADERS)
 ifdef OW
-	wcl $(if $(GAS),-DSYNTAX_GAS=1,) $(if $(DEBUG),-DDEBUG=1,) -fe="ntc.exe" -0 -bcl=dos -mt $(if $(DEBUG),,-d0 -os -om -ob -oi -ol -ox) -lr -za99 -i=src $(SOURCES)
+	wcl386 -ml $(if $(GAS),-DSYNTAX_GAS=1,) $(if $(DEBUG),-DDEBUG=1,) -fe="ntc.exe" -bt=dos -l=dos4g -ml $(if $(DEBUG),,-d0 -os -om -ob -oi -ol -ox) -lr -za99 -i=src $(SOURCES)
 else
 	cc $(if $(GAS),-DSYNTAX_GAS=1,) $(if $(DEBUG),-DDEBUG=1,) -Wall -o ntc -fno-PIE -no-pie -std=gnu11 $(if $(DEBUG),-O0 -g,-Os -s) -fms-extensions -Isrc $(SOURCES)
 endif

README.md

@@ -1,11 +1,19 @@
 # N19 Reference Compiler
 
-Made to compile fast and produce not great, but acceptable output. Currently only 386 output supported (protected and partially real mode).
+Made to compile fast and produce acceptable output. Currently only 386 output supported (protected and partially real mode).
+
+Composed of the following passes:
+
+1. Lexing
+2. Parsing & loop\_second\_pass
+3. Dumbification
+4. Codegen
+
+UD-chains are generated during parsing. Codegen uses on primitive patterns within the AST, possible thanks to dumbification. This technique is applicable owing to Nectar's already low-level nature
 
 # Installation
 
     make
-    
     sudo make install
 
 # Command-line usage

src/ast.c

@@ -4,14 +4,6 @@
 #include<string.h>
 #include<stdlib.h>
 
-int BINOP_COMMUTATIVE[] = {
-	[BINOP_ADD] = 1,
-	[BINOP_SUB] = 0,
-	[BINOP_MUL] = 1,
-	[BINOP_DIV] = 0
-};
-
-
 AST *ast_expression_optimize(AST *ast) {
 	return ast;
 }
@@ -37,6 +29,13 @@ int ast_stmt_is_after(const AST *chunk, const AST *s1, const AST *s2) {
 	const AST *s = chunk->chunk.statementFirst;
 	
 	while(s) {
+		if(s->nodeKind == AST_STMT_LOOP) {
+			int i = ast_stmt_is_after(s->stmtLoop.body, s1, s2);
+			if(i != -1) {
+				return i;
+			}
+		}
+		
 		if(s == s1) {
 			return 0;
 		}
@@ -49,11 +48,6 @@ int ast_stmt_is_after(const AST *chunk, const AST *s1, const AST *s2) {
 			if(i != -1) {
 				return i;
 			}
-		} else if(s->nodeKind == AST_STMT_LOOP) {
-			int i = ast_stmt_is_after(s->stmtLoop.body, s1, s2);
-			if(i != -1) {
-				return i;
-			}
 		}
 		
 		s = s->statement.next;

src/ast.h

@@ -5,7 +5,20 @@
 #include"lexer.h"
 #include"vartable.h"
 
-typedef enum {
+// VISITORS APPEAR IN varify_change_usedefs,ast_expr_is_equal,ast_stmt_is_after,
+// dumben_chunk, cg_go, loop_second_pass AND OTHERS
+//
+// THEY ***MUST*** BE CHANGED ACCORDINGLY IF AST IS ALTERED
+
+#pragma pack(push, 1)
+
+#ifdef __GNUC__
+#define ENUMPAK __attribute__((packed))
+#else
+#define ENUMPAK
+#endif
+
+typedef enum ENUMPAK {
 	AST_CHUNK,
 	AST_STMT_DECL,
 	AST_TYPE_IDENTIFIER,
@@ -29,7 +42,7 @@ typedef enum {
 	AST_STMT_EXT_SECTION,
 } ASTKind;
 
-typedef enum {
+typedef enum ENUMPAK {
 	BINOP_ADD = 0,
 	BINOP_SUB = 1,
 	BINOP_BITWISE_AND = 2,
@@ -44,7 +57,6 @@ typedef enum {
 	
 	BINOP_WTF = 999,
 } BinaryOp;
-extern int BINOP_COMMUTATIVE[];
 
 static inline int binop_is_comparison(BinaryOp op) {
 	return op == BINOP_EQUAL || op == BINOP_NEQUAL;
@@ -59,7 +71,7 @@ static inline BinaryOp binop_comp_opposite(BinaryOp op) {
 	return BINOP_WTF;
 }
 
-typedef enum {
+typedef enum ENUMPAK {
 	UNOP_DEREF = 0,
 	UNOP_NEGATE = 1,
 	UNOP_BITWISE_NOT = 2,
@@ -251,6 +263,8 @@ typedef union AST {
 	ASTStmtExtSection stmtExtSection;
 } AST;
 
+#pragma pack(pop)
+
 AST *ast_expression_optimize(AST*);
 int ast_expression_equal(AST*, AST*);
 

src/cg.c

@@ -5,14 +5,16 @@
 #include<string.h>
 #include<assert.h>
 
+#include"x86.h"
+
 #define REGS 4
-static const char *regs[REGS][3] = {{"al", "ax", "eax"}, {"bl", "bx", "ebx"}, {"cl", "cx", "ecx"}, {"dl", "dx", "edx"}, {"sil", "si", "esi"}, {"dil", "di", "edi"}};
+static const char *regs[REGS][3] = {{"al", "ax", "eax"}, {"bl", "bx", "ebx"}, {"cl", "cx", "ecx"}, {"dl", "dx", "edx"}};
 
 static const char *BINOP_SIMPLE_INSTRS[] = {[BINOP_ADD] = "add", [BINOP_SUB] = "sub", [BINOP_BITWISE_AND] = "and", [BINOP_BITWISE_OR] = "or", [BINOP_BITWISE_XOR] = "xor"};
 
 static size_t nextLocalLabel = 0;
 
-#define LOOPSTACKSIZE 64
+#define LOOPSTACKSIZE 96
 static size_t loopStackStart[LOOPSTACKSIZE];
 static size_t loopStackEnd[LOOPSTACKSIZE];
 static size_t loopStackIdx;
@@ -37,11 +39,21 @@ static const char *spec(int size) {
 	abort();
 }
 
+static int log_size(int size) {
+	switch(size) {
+	case 1: return 0;
+	case 2: return 1;
+	case 4: return 2;
+	case 8: return 3;
+	}
+	abort();
+}
+
 static const char *specexpr(AST *e) {
 	return spec(type_size(e->expression.type));
 }
 
-static const char *xv(VarTableEntry *v) {
+static const char *xv_sz(VarTableEntry *v, int sz) {
 	assert(v->kind == VARTABLEENTRY_VAR);
 	
 #define XVBUFS 8
@@ -54,7 +66,7 @@ static const char *xv(VarTableEntry *v) {
 #ifdef DEBUG
 	snprintf(ret, XVBUFSZ, "@%i", v->data.var.color);
 #else
-	snprintf(ret, XVBUFSZ, "%s", regs[v->data.var.color][2]);
+	snprintf(ret, XVBUFSZ, "%s", regs[v->data.var.color][log_size(sz)]);
 #endif
 	
 	bufidx = (bufidx + 1) % XVBUFS;
@@ -62,6 +74,10 @@ static const char *xv(VarTableEntry *v) {
 	return ret;
 }
 
+static const char *xv(VarTableEntry *v) {
+	return xv_sz(v, type_size(v->type));
+}
+
 static const char *xj(BinaryOp op) {
 	switch(op) {
 	case BINOP_EQUAL: return "e";
@@ -70,7 +86,7 @@ static const char *xj(BinaryOp op) {
 	}
 }
 
-static const char *xop(AST *e) {
+static const char *xop_sz(AST *e, int sz) {
 #define XOPBUFS 16
 #define XOPBUFSZ 24
 	static char bufs[XOPBUFS][XOPBUFSZ];
@@ -82,25 +98,32 @@ static const char *xop(AST *e) {
 		VarTableEntry *v = e->exprVar.thing;
 		
 		if(v->kind == VARTABLEENTRY_VAR) {
-			return xv(v);
+			return xv_sz(v, sz);
 		} else if(v->kind == VARTABLEENTRY_SYMBOL) {
 			snprintf(ret, XOPBUFSZ, "[%s]", v->data.symbol.name);
 		} else abort();
 	} else if(e->nodeKind == AST_EXPR_PRIMITIVE) {
 		snprintf(ret, XOPBUFSZ, "%i", e->exprPrim.val);
+	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF && e->exprUnOp.operand->nodeKind == AST_EXPR_BINARY_OP && e->exprUnOp.operand->exprBinOp.operator == BINOP_ADD && e->exprUnOp.operand->exprBinOp.operands[0]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[0]->exprVar.thing->kind == VARTABLEENTRY_VAR && e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
+		snprintf(ret, XOPBUFSZ, "%s [%s + %s]",
+			spec(sz),
+			xv_sz(e->exprUnOp.operand->exprBinOp.operands[0]->exprVar.thing, 4),
+			xv_sz(e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing, 4));
 	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF && e->exprUnOp.operand->nodeKind == AST_EXPR_BINARY_OP && e->exprUnOp.operand->exprBinOp.operator == BINOP_ADD && e->exprUnOp.operand->exprBinOp.operands[0]->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operand->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operator == UNOP_REF && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL && e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
-		snprintf(ret, XOPBUFSZ, "[%s + %s]",
+		snprintf(ret, XOPBUFSZ, "%s [%s + %s]",
+			spec(sz),
 			e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->data.symbol.name,
-			xv(e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing));
+			xv_sz(e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing, 4));
 	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF && e->exprUnOp.operand->nodeKind == AST_EXPR_BINARY_OP && e->exprUnOp.operand->exprBinOp.operator == BINOP_ADD && e->exprUnOp.operand->exprBinOp.operands[0]->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operand->exprBinOp.operands[1]->nodeKind == AST_EXPR_BINARY_OP && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operator == UNOP_REF && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL && e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operator == BINOP_MUL && e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[0]->nodeKind == AST_EXPR_PRIMITIVE && e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
-		snprintf(ret, XOPBUFSZ, "[%s + %i * %s]",
+		snprintf(ret, XOPBUFSZ, "%s [%s + %i * %s]",
+			spec(sz),
 			e->exprUnOp.operand->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->data.symbol.name,
 			e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[0]->exprPrim.val,
-			xv(e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[1]->exprVar.thing));
+			xv_sz(e->exprUnOp.operand->exprBinOp.operands[1]->exprBinOp.operands[1]->exprVar.thing, 4));
 	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_REF && e->exprUnOp.operand->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL) {
 		snprintf(ret, XOPBUFSZ, "%s", e->exprUnOp.operand->exprVar.thing->data.symbol.name);
 	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF && e->exprUnOp.operand->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_VAR) {
-		snprintf(ret, XOPBUFSZ, "[%s]", xv(e->exprUnOp.operand->exprVar.thing));
+		snprintf(ret, XOPBUFSZ, "%s [%s]", spec(sz), xv_sz(e->exprUnOp.operand->exprVar.thing, 4));
 	} else {
 		return NULL;
 	}
@@ -110,6 +133,10 @@ static const char *xop(AST *e) {
 	return ret;
 }
 
+static const char *xop(AST *e) {
+	return xop_sz(e, type_size(e->expression.type));
+}
+
 void cg_chunk(AST *a) {
 	AST *s = a->chunk.statementFirst;
 	
@@ -124,6 +151,16 @@ void cg_chunk(AST *a) {
 		
 			printf("org %lu\n", s->stmtExtOrg.val);
 			
+		} else if(s->nodeKind == AST_STMT_EXT_ALIGN) {
+		
+			uint32_t val = s->stmtExtAlign.val;
+			if((val & (val - 1))) {
+				// nasm does not support non-PoT alignments, so pad manually
+				printf("times ($ - $$ + %u) / %u * %u - ($ - $$) db 0\n", val - 1, val, val);
+			} else {
+				printf("align %u\n", val);
+			}
+			
 		} else if(s->nodeKind == AST_STMT_DECL && s->stmtDecl.thing->kind == VARTABLEENTRY_SYMBOL) {
 			VarTableEntry *v = s->stmtDecl.thing;
 			
@@ -135,38 +172,72 @@ void cg_chunk(AST *a) {
 				}
 				
 				if(s->stmtDecl.expression) {
-					puts("A");
+					printf("%s:", v->data.symbol.name);
+					if(v->type->type == TYPE_TYPE_PRIMITIVE) {
+					
+						assert(s->stmtDecl.expression->nodeKind == AST_EXPR_PRIMITIVE);
+						
+						printf("%s %i", direct(type_size(v->type)), s->stmtDecl.expression->exprPrim.val);
+						
+					} else if(v->type->type == TYPE_TYPE_ARRAY && v->type->array.of->type == TYPE_TYPE_PRIMITIVE) {
+					
+						printf("%s ", direct(type_size(v->type->array.of)));
+						for(size_t i = 0; i < v->type->array.length; i++) {
+							printf("%i,", s->stmtDecl.expression->exprArray.items[i]->exprPrim.val);
+						}
+						
+					} else printf("A");
+					putchar('\n');
 				} else {
+				
 					printf("%s resb %lu\n", v->data.symbol.name, type_size(s->stmtDecl.thing->type));
+					
 				}
 			}
 		} else if(s->nodeKind == AST_STMT_ASSIGN) {
 			
-			if(s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && ast_expression_equal(s->stmtAssign.what, s->stmtAssign.to->exprBinOp.operands[0]) && (s->stmtAssign.to->exprBinOp.operator == BINOP_ADD || s->stmtAssign.to->exprBinOp.operator == BINOP_SUB) && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_PRIMITIVE && s->stmtAssign.to->exprBinOp.operands[1]->exprPrim.val == 1) {
+			if(s->stmtAssign.to) {
+				if(s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && ast_expression_equal(s->stmtAssign.what, s->stmtAssign.to->exprBinOp.operands[0]) && (s->stmtAssign.to->exprBinOp.operator == BINOP_ADD || s->stmtAssign.to->exprBinOp.operator == BINOP_SUB) && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_PRIMITIVE && s->stmtAssign.to->exprBinOp.operands[1]->exprPrim.val == 1) {
 				
-				// inc or dec
+					// inc or dec
 					
-				static const char *instrs[] = {"inc", "dec"};
+					static const char *instrs[] = {"inc", "dec"};
-				printf("%s %s %s\n", instrs[s->stmtAssign.to->exprBinOp.operator == BINOP_SUB], specexpr(s->stmtAssign.what), xop(s->stmtAssign.what));
+					printf("%s %s %s\n", instrs[s->stmtAssign.to->exprBinOp.operator == BINOP_SUB], specexpr(s->stmtAssign.what), xop(s->stmtAssign.what));
 					
-			} else if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && s->stmtAssign.to->exprBinOp.operator == BINOP_ADD && s->stmtAssign.to->exprBinOp.operands[0]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing->kind == VARTABLEENTRY_VAR && s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
+				} else if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && s->stmtAssign.to->exprBinOp.operator == BINOP_ADD && s->stmtAssign.to->exprBinOp.operands[0]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing->kind == VARTABLEENTRY_VAR && s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
 					
-				printf("lea %s, [%s + %s]\n",
+					printf("lea %s, [%s + %s]\n",
-					xv(s->stmtAssign.what->exprVar.thing),
+						xv(s->stmtAssign.what->exprVar.thing),
-					xv(s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing),
+						xv(s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing),
-					xv(s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing));
+						xv(s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing));
 					
-			} else if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && s->stmtAssign.to->exprBinOp.operator == BINOP_ADD && s->stmtAssign.to->exprBinOp.operands[0]->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operator == UNOP_REF && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL && s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
+				} else if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && s->stmtAssign.to->exprBinOp.operator == BINOP_ADD && s->stmtAssign.to->exprBinOp.operands[0]->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operator == UNOP_REF && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL && s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
 					
-				printf("lea %s, [%s + %s]\n",
+					printf("lea %s, [%s + %s]\n",
-					xv(s->stmtAssign.what->exprVar.thing),
+						xv(s->stmtAssign.what->exprVar.thing),
-					s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->data.symbol.name,
+						s->stmtAssign.to->exprBinOp.operands[0]->exprUnOp.operand->exprVar.thing->data.symbol.name,
-					xv(s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing));
+						xv(s->stmtAssign.to->exprBinOp.operands[1]->exprVar.thing));
 					
-			} else {
+				} else if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_BINARY_OP && s->stmtAssign.to->exprBinOp.operator == BINOP_ADD && s->stmtAssign.to->exprBinOp.operands[0]->nodeKind == AST_EXPR_VAR && s->stmtAssign.to->exprBinOp.operands[1]->nodeKind == AST_EXPR_PRIMITIVE && s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
 					
-				printf("mov %s, %s\n", xop(s->stmtAssign.what), xop(s->stmtAssign.to));
+					printf("lea %s, [%s + %i]\n",
+						xv_sz(s->stmtAssign.what->exprVar.thing, 4),
+						xv_sz(s->stmtAssign.to->exprBinOp.operands[0]->exprVar.thing, 4),
+						s->stmtAssign.to->exprBinOp.operands[1]->exprPrim.val);
 				
+				} else if(is_xop(s->stmtAssign.what) != NULL && s->stmtAssign.to->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.to->exprUnOp.operator == UNOP_NEGATE && ast_expression_equal(s->stmtAssign.what, s->stmtAssign.to->exprUnOp.operand)) {
+					
+					printf("neg %s\n", xop(s->stmtAssign.what));
+					
+				} else {
+				
+					if(is_xop(s->stmtAssign.to) == XOP_MEM && type_size(s->stmtAssign.what->expression.type) != type_size(s->stmtAssign.to->expression.type)) {
+						printf("movzx %s, %s\n", xop_sz(s->stmtAssign.what, 4), xop_sz(s->stmtAssign.to, type_size(s->stmtAssign.what->expression.type)));
+					} else {
+						printf("mov %s, %s\n", xop(s->stmtAssign.what), xop_sz(s->stmtAssign.to, type_size(s->stmtAssign.what->expression.type)));
+					}
+					
+				}
 			}
 			
 		} else if(s->nodeKind == AST_STMT_LOOP) {
@@ -202,7 +273,7 @@ void cg_chunk(AST *a) {
 			
 			size_t lbl = nextLocalLabel++;
 			
-			printf("cmp %s %s, %s\n", specexpr(s->stmtIf.expression->exprBinOp.operands[0]), xop(s->stmtIf.expression->exprBinOp.operands[0]), xop(s->stmtIf.expression->exprBinOp.operands[1]));
+			printf("cmp %s, %s\n", xop(s->stmtIf.expression->exprBinOp.operands[0]), xop(s->stmtIf.expression->exprBinOp.operands[1]));
 			printf("j%s .L%lu\n", xj(binop_comp_opposite(s->stmtIf.expression->exprBinOp.operator)), lbl);
 			
 			cg_chunk(s->stmtIf.then);

src/dumberdowner.c

@@ -0,0 +1,308 @@
+#include"dumberdowner.h"
+
+#include<stdlib.h>
+#include<assert.h>
+
+// This is the dumbing down pass.
+//
+// Complex expressions are to be "broken down" into simpler ones until the AST
+// can be trivially translated to the target architecture.
+//
+// This pass, along with CG is strictly dependent on x86 and will fail for
+// any other architecture.
+
+#include"x86.h"
+
+static void varify_change_usedefs(AST *e, AST *oldStmt, AST *newStmt) {
+	if(e->nodeKind == AST_EXPR_VAR) {
+		if(e->exprVar.thing->kind != VARTABLEENTRY_VAR) {
+			return;
+		}
+		
+		UseDef *swapWithPrev = NULL;
+		UseDef *swapWith = NULL;
+		
+		UseDef *udPrev = NULL;
+		UseDef *ud = e->exprVar.thing->data.var.usedefFirst;
+		while(ud && ud->use != e) {
+			if(ud->stmt == oldStmt && !swapWith) {
+				swapWithPrev = udPrev;
+				swapWith = ud;
+			}
+			
+			udPrev = ud;
+			ud = ud->next;
+		}
+		
+		if(ud) {
+			assert(ud->stmt == oldStmt);
+			ud->stmt = newStmt;
+			
+			// We must make sure all newStmt usedefs are before the oldStmt ones, so swap
+			if(swapWith) {
+				assert(!!swapWithPrev + !!udPrev != 0);
+				
+				if(swapWithPrev) {
+					swapWithPrev->next = ud;
+				} else {
+					e->exprVar.thing->data.var.usedefFirst = ud;
+				}
+				
+				if(udPrev) {
+					udPrev->next = swapWith;
+				} else {
+					e->exprVar.thing->data.var.usedefFirst = swapWith;
+				}
+				
+				UseDef *temp = ud->next;
+				ud->next = swapWith->next;
+				swapWith->next = temp;
+				
+				assert(!!ud->next + !!swapWith->next != 0);
+				if(!swapWith->next) {
+					e->exprVar.thing->data.var.usedefLast = swapWith;
+				}
+				if(!ud->next) {
+					e->exprVar.thing->data.var.usedefLast = ud;
+				}
+			}
+		}
+	} else if(e->nodeKind == AST_EXPR_BINARY_OP) {
+		varify_change_usedefs(e->exprBinOp.operands[0], oldStmt, newStmt);
+		varify_change_usedefs(e->exprBinOp.operands[1], oldStmt, newStmt);
+	} else if(e->nodeKind == AST_EXPR_UNARY_OP) {
+		varify_change_usedefs(e->exprUnOp.operand, oldStmt, newStmt);
+	} else if(e->nodeKind == AST_EXPR_CALL) {
+		varify_change_usedefs(e->exprCall.what, oldStmt, newStmt);
+		
+		int argCount = e->exprCall.what->expression.type->function.argCount;
+		for(int i = 0; i < argCount; i++) {
+			varify_change_usedefs(e->exprCall.args[i], oldStmt, newStmt);
+		}
+	} else if(e->nodeKind == AST_EXPR_ARRAY) {
+		int sz = e->exprArray.type->array.length;
+		for(int i = 0; i < sz; i++) {
+			varify_change_usedefs(e->exprArray.items[i], oldStmt, newStmt);
+		}
+	} else if(e->nodeKind == AST_EXPR_CAST) {
+		varify_change_usedefs(e->exprCast.what, oldStmt, newStmt);
+	}
+}
+
+/* Split away complex expression into a new local variable */
+static AST *varify(AST *tlc, AST *chunk, AST *stmtPrev, AST *stmt, AST *e) {
+	VarTableEntry *vte = malloc(sizeof(*vte));
+	vte->kind = VARTABLEENTRY_VAR;
+	vte->type = e->expression.type;
+	vte->data.var.color = 0;
+	vte->data.var.degree = 0;
+	vte->data.var.priority = 0;
+	vte->data.var.reachingDefs = NULL;
+	
+	// Add to var array
+	tlc->chunk.vars = realloc(tlc->chunk.vars, sizeof(*tlc->chunk.vars) * (++tlc->chunk.varCount));
+	tlc->chunk.vars[tlc->chunk.varCount - 1] = vte;
+	
+	// Alter AST
+	
+	ASTExprVar *ev[2];
+	for(int i = 0; i < 2; i++) {
+		ev[i] = malloc(sizeof(ASTExprVar));
+		ev[i]->nodeKind = AST_EXPR_VAR;
+		ev[i]->type = e->expression.type;
+		ev[i]->thing = vte;
+	}
+	
+	ASTStmtAssign *assign = malloc(sizeof(*assign));
+	assign->nodeKind = AST_STMT_ASSIGN;
+	assign->what = (AST*) ev[0];
+	assign->to = e;
+	
+	if(stmtPrev) {
+		stmtPrev->statement.next = (AST*) assign;
+	} else {
+		chunk->chunk.statementFirst = (AST*) assign;
+	}
+	assign->next = stmt;
+	
+	// Assemble ud-chain
+	
+	UseDef *ud[2];
+	ud[0] = malloc(sizeof(UseDef));
+	ud[1] = malloc(sizeof(UseDef));
+	
+	ud[0]->stmt = (AST*) assign;
+	ud[0]->use = assign->what;
+	ud[0]->def = (AST*) assign;
+	ud[0]->next = ud[1];
+	
+	ud[1]->stmt = stmt;
+	ud[1]->use = (AST*) ev[1];
+	ud[1]->def = (AST*) assign;
+	ud[1]->next = NULL;
+	
+	vte->data.var.usedefFirst = ud[0];
+	vte->data.var.usedefLast = ud[1];
+	
+	// Correct the ud-chain of variables used in varified expression `e`
+	
+	varify_change_usedefs(e, stmt, (AST*) assign);
+	
+	return (AST*) ev[1];
+}
+
+static AST *xopify(AST *tlc, AST *chunk, AST *stmtPrev, AST *stmt, AST *e) {
+	return varify(tlc, chunk, stmtPrev, stmt, e);
+}
+
+static UseDef *get_last_usedef_before_stmt(AST *tlc, VarTableEntry *v, AST *stmt) {
+	assert(v->kind == VARTABLEENTRY_VAR);
+	
+	UseDef *ud = v->data.var.usedefFirst;
+	
+	if(!ud) {
+		return NULL;
+	}
+	
+	UseDef *udPrev = NULL;
+	
+	while(ud) {
+		if(ast_stmt_is_after(tlc, ud->stmt, stmt)) {
+			break;
+		}
+		udPrev = ud;
+		ud = ud->next;
+	}
+	
+	return udPrev;
+}
+
+static int dumben_chunk(AST *tlc, AST *chu) {
+	AST *sPrev = NULL;
+	AST *s = chu->chunk.statementFirst;
+	
+	int effective = 0;
+	
+	while(s) {
+	
+		if(s->nodeKind == AST_STMT_IF) {
+			
+			AST *e = s->stmtIf.expression;
+			
+			if(e->nodeKind == AST_EXPR_BINARY_OP && binop_is_comparison(e->exprBinOp.operator)) {
+			
+				if(is_xop(e->exprBinOp.operands[0]) == XOP_NOT_XOP) {
+					e->exprBinOp.operands[0] = xopify(tlc, chu, sPrev, s, e->exprBinOp.operands[0]);
+					effective = 1;
+				}
+				
+				if(is_xop(e->exprBinOp.operands[1]) == XOP_NOT_XOP) {
+					e->exprBinOp.operands[1] = xopify(tlc, chu, sPrev, s, e->exprBinOp.operands[1]);
+					effective = 1;
+				}
+				
+				if(is_xop(e->exprBinOp.operands[0]) == XOP_MEM && is_xop(e->exprBinOp.operands[1]) == XOP_MEM) {
+					// Can't have two mems; put one in var
+					
+					e->exprBinOp.operands[1] = varify(tlc, chu, sPrev, s, e->exprBinOp.operands[1]);
+					effective = 1;
+				}
+				
+			} else {
+				
+				s->stmtIf.expression = varify(tlc, chu, sPrev, s, e);
+				effective = 1;
+				
+			}
+			
+			effective |= dumben_chunk(tlc, s->stmtIf.then);
+			
+		} else if(s->nodeKind == AST_STMT_LOOP) {
+			
+			effective |= dumben_chunk(tlc, s->stmtLoop.body);
+			
+		} else if(s->nodeKind == AST_STMT_ASSIGN) {
+			
+			if(s->stmtAssign.what->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.what->exprUnOp.operator == UNOP_DEREF
+				&& s->stmtAssign.to->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.to->exprUnOp.operator == UNOP_DEREF) {
+				
+				s->stmtAssign.to = varify(tlc, chu, sPrev, s, s->stmtAssign.to);
+				effective = 1;
+			}
+			
+			if(s->stmtAssign.what->nodeKind == AST_EXPR_VAR && s->stmtAssign.what->exprVar.thing->kind == VARTABLEENTRY_VAR && s->stmtAssign.to->nodeKind == AST_EXPR_UNARY_OP && s->stmtAssign.to->exprUnOp.operator == UNOP_NEGATE && (s->stmtAssign.to->exprUnOp.operand->nodeKind != AST_EXPR_VAR || s->stmtAssign.what->exprVar.thing != s->stmtAssign.to->exprUnOp.operand->exprVar.thing)) {
+				// Turn this:
+				//  a = -b
+				// into
+				//  a = b
+				//  a = -a
+				// While keeping UD-chain valid.
+				
+				// Currently only for variables. While this could work for any XOP, it requires the ability to deep-copy `a`, which is not trivial when taking into account UD-chains.
+				// TODO: Scrap incremental UD-chain modifications. Simply rebuild them after each pass.
+				
+				ASTExprVar *ev[2];
+				for(int i = 0; i < 2; i++) {
+					ev[i] = malloc(sizeof(ASTExprVar));
+					ev[i]->nodeKind = AST_EXPR_VAR;
+					ev[i]->type = s->stmtAssign.what->expression.type;
+					ev[i]->thing = s->stmtAssign.what->exprVar.thing;
+				}
+				
+				AST *negation = s->stmtAssign.to;
+				
+				s->stmtAssign.to = negation->exprUnOp.operand;
+				negation->exprUnOp.operand = ev[0];
+				
+				AST *assign2 = malloc(sizeof(ASTStmtAssign));
+				assign2->nodeKind = AST_STMT_ASSIGN;
+				assign2->stmtAssign.what = ev[1];
+				assign2->stmtAssign.to = negation;
+				
+				assign2->statement.next = s->statement.next;
+				s->statement.next = assign2;
+
+				UseDef *link = get_last_usedef_before_stmt(tlc, ev[0]->thing, assign2->statement.next);
+				
+				UseDef *ud[2];
+				ud[0] = malloc(sizeof(UseDef));
+				ud[1] = malloc(sizeof(UseDef));
+
+				ud[0]->stmt = assign2;
+				ud[0]->use = (AST*) ev[1];
+				ud[0]->def = s;
+				ud[0]->next = ud[1];
+
+				ud[1]->stmt = assign2;
+				ud[1]->use = (AST*) ev[0];
+				ud[1]->def = s;
+				ud[1]->next = link->next;
+				
+				link->next = ud[0];
+				
+				effective = 1;
+			}
+			
+		} else if(s->nodeKind == AST_STMT_EXPR && s->stmtExpr.expr->nodeKind == AST_EXPR_CALL) {
+			
+			int argCount = s->stmtExpr.expr->exprCall.what->expression.type->function.argCount;
+			
+			for(int i = 0; i < argCount; i++) {
+				if(is_xop(s->stmtExpr.expr->exprCall.args[i]) == XOP_NOT_XOP) {
+					s->stmtExpr.expr->exprCall.args[i] = xopify(tlc, chu, sPrev, s, s->stmtExpr.expr->exprCall.args[i]);
+					effective = 1;
+				}
+			}
+			
+		}
+		
+		sPrev = s;
+		s = s->statement.next;
+	}
+	
+	return effective;
+}
+
+void dumben_go(AST* tlc) {
+	while(dumben_chunk(tlc, tlc));
+}

src/dumberdowner.h

@@ -0,0 +1,5 @@
+#pragma once
+
+#include"ast.h"
+
+void dumben_go(AST* a);

src/lexer.c

@@ -318,3 +318,10 @@ Token *nct_lex(FILE *f) {
 	
 	return NULL; /* Doesn't reach here. */
 }
+
+void nct_lex_free(Token *tokens) {
+	for(Token *t = tokens; t->type != TOKEN_EOF; t++) {
+		if(t->content) free(t->content);
+	}
+	free(tokens);
+}

src/lexer.h

@@ -50,5 +50,6 @@ typedef struct {
 
 Token nct_tokenize(FILE*);
 Token *nct_lex(FILE*);
+void nct_lex_free(Token *);
 
 #endif

src/ntc.c

@@ -7,6 +7,7 @@
 #include"ntc.h"
 #include"reporting.h"
 #include"cg.h"
+#include"dumberdowner.h"
 
 static int argc;
 static char **argv;
@@ -36,6 +37,8 @@ int main(int argc_, char **argv_) {
 	
 	free(tokens);
 	
+	dumben_go(chunk);
+	
 	cg_go(chunk);
 	
 	return 0;

src/parse.c

@@ -9,6 +9,21 @@
 #include<stdint.h>
 #include<signal.h>
 
+#ifndef __GNUC__
+static inline int __builtin_clzl(unsigned long x) {
+	unsigned long n = 32;
+	unsigned long y;
+
+	y = x >>16; if (y != 0) { n = n -16; x = y; }
+	y = x >> 8; if (y != 0) { n = n - 8; x = y; }
+	y = x >> 4; if (y != 0) { n = n - 4; x = y; }
+	y = x >> 2; if (y != 0) { n = n - 2; x = y; }
+	y = x >> 1; if (y != 0) return n - 2;
+	
+	return n - x;
+}
+#endif
+
 typedef struct {
 	UseDef ud;
 	VarTableEntry *to;
@@ -16,7 +31,7 @@ typedef struct {
 
 typedef struct {
 	Token *tokens;
-	ssize_t i;
+	intmax_t i;
 	
 	VarTable *scope;
 	
@@ -29,6 +44,11 @@ typedef struct {
 	// Used by pushstmt to assemble use-def chain
 	size_t udsToAddCount;
 	UseDefToAdd *udsToAdd;
+	
+	// Used to place guard variable uses after loops to stop reg allocation from fucking up
+	VarTable *loopScope;
+	size_t guardedVarCount;
+	ASTExprVar **guardedVars;
 } Parser;
 
 static Token get(Parser *P) {
@@ -75,6 +95,11 @@ static void pushstat(Parser *P, void *a) {
 		memcpy(ud, &P->udsToAdd[i].ud, sizeof(*ud));
 		ud->stmt = a;
 		
+		/*if(ud->stmt->nodeKind == AST_STMT_ASSIGN && ud->stmt->stmtAssign.what == ud->use) {
+			// Forget. The x in `x = y` is not a use of x.
+			continue;
+		}*/
+		
 		if(to->data.var.usedefFirst) {
 			to->data.var.usedefLast->next = ud;
 			to->data.var.usedefLast = ud;
@@ -96,7 +121,6 @@ static void pushstat(Parser *P, void *a) {
 static ASTExprPrimitive *parse_prim(Parser *P) {
 	ASTExprPrimitive *ret = malloc(sizeof(*ret));
 	ret->nodeKind = AST_EXPR_PRIMITIVE;
-	ret->type = (Type*) primitive_parse("s16");
 	
 	Token tok = get(P);
 	
@@ -109,21 +133,32 @@ static ASTExprPrimitive *parse_prim(Parser *P) {
 	
 	ret->val = strtol(str, NULL, base);
 	
+	// Smallest integer type to store number
+	char buf[8];
+	snprintf(buf, sizeof(buf), "s%i", ret->val ? (64 - __builtin_clzl(ret->val - 1)) : 1);
+	ret->type = (Type*) primitive_parse(buf);
+	
 	return ret;
 }
 
 static void newusedef(Parser *P, VarTableEntry *v, AST *expr) {
-	for(size_t i = 0; i < v->data.var.reachingDefs->defCount; i++) {
+	ReachingDefs *defs = v->data.var.reachingDefs;
-		P->udsToAdd = realloc(P->udsToAdd, sizeof(*P->udsToAdd) * (++P->udsToAddCount));
+	
-		P->udsToAdd[P->udsToAddCount - 1] = (UseDefToAdd) {
+	while(defs) {
-			.ud = {
+		for(size_t i = 0; i < defs->defCount; i++) {
-				.def = v->data.var.reachingDefs->defs[i],
+			P->udsToAdd = realloc(P->udsToAdd, sizeof(*P->udsToAdd) * (++P->udsToAddCount));
-				.use = expr,
+			P->udsToAdd[P->udsToAddCount - 1].ud.def = defs->defs[i];
-				.stmt = NULL, // set by pushstmt
+			P->udsToAdd[P->udsToAddCount - 1].ud.use = expr;
-				.next = NULL,
+			P->udsToAdd[P->udsToAddCount - 1].ud.stmt = NULL; // set by pushstmt
-			},
+			P->udsToAdd[P->udsToAddCount - 1].ud.next = NULL;
-			.to = v
+			P->udsToAdd[P->udsToAddCount - 1].to = v;
-		};
+		}
+		
+		if(defs->excludeParent) {
+			break;
+		}
+		
+		defs = defs->parent;
 	}
 }
 
@@ -137,6 +172,36 @@ static AST *exprvar(Parser *P, VarTableEntry *v) {
 		newusedef(P, v, a);
 	}
 	
+	if(P->loopScope) {
+		// XXX: O(n)!!!!!!!!!
+		
+		int inloop = 0;
+		for(VarTable *vt = v->owner; vt; vt = vt->parent) {
+			if(vt->parent == P->loopScope) {
+				inloop = 1;
+				break;
+			}
+		}
+		
+		if(!inloop) {
+			int alreadyAdded = 0;
+			for(size_t i = 0; i < P->guardedVarCount; i++) {
+				if(P->guardedVars[i]->thing == v) {
+					alreadyAdded = 1;
+					break;
+				}
+			}
+			
+			if(!alreadyAdded) {
+				ASTExprVar *ev = malloc(sizeof(*ev));
+				memcpy(ev, a, sizeof(*ev));
+				
+				P->guardedVars = realloc(P->guardedVars, sizeof(*P->guardedVars) * (P->guardedVarCount + 1));
+				P->guardedVars[P->guardedVarCount++] = ev;
+			}
+		}
+	}
+	
 	return a;
 }
 
@@ -163,10 +228,14 @@ AST *nct_cast_expr(AST *what, Type *to) {
 			}
 			
 			return (AST*) ret;
-		} else if(to->type == TYPE_TYPE_PRIMITIVE && to->primitive.width == 32) {
+		} else if(to->type == TYPE_TYPE_PRIMITIVE) {
+			if(to->primitive.width != what->exprStrLit.length * 8) {
+				stahp(0, 0, "Size mismatch between string literal and target type");
+			}
+			
 			ASTExprPrimitive *ret = malloc(sizeof(*ret));
 			ret->nodeKind = AST_EXPR_PRIMITIVE;
-			ret->type = primitive_parse("u32");
+			ret->type = to;
 			memcpy(&ret->val, what->exprStrLit.data, sizeof(ret->val));
 			return (AST*) ret;
 		} else abort();
@@ -185,6 +254,9 @@ AST *nct_cast_expr(AST *what, Type *to) {
 		ret->val = what->exprPrim.val & (((int64_t) 1 << to->primitive.width) - 1);
 		return (AST*) ret;
 	} else {
+		// Silently fail :)
+		return what;
+		
 		ASTExprCast *ret = malloc(sizeof(*ret));
 		ret->nodeKind = AST_EXPR_CAST;
 		ret->type = to;
@@ -213,6 +285,10 @@ AST *nct_parse_expression(Parser *P, int lOP) {
 			ret->length = tok.length;
 			
 			return (AST*) ret;
+		} else if(maybe(P, TOKEN_PAREN_L)) {
+			AST *e = nct_parse_expression(P, 0);
+			expect(P, TOKEN_PAREN_R);
+			return e;
 		}
 	} else if(lOP == 4) {
 		if(maybe(P, TOKEN_STAR)) {
@@ -577,6 +653,7 @@ static AST *parse_declaration(Parser *P) {
 		
 		ASTStmtAssign *assign = malloc(sizeof(*assign));
 		assign->nodeKind = AST_STMT_ASSIGN;
+		assign->next = NULL;
 		
 		entry->data.var.reachingDefs = reachingdefs_push(NULL);
 		reachingdefs_set(entry->data.var.reachingDefs, (AST*) assign);
@@ -633,6 +710,77 @@ backtrack:
 	return NULL;
 }
 
+/*	Imagine the following pseudocode:
+	x = ...
+	while ... {
+		(do something with x)
+		x = ...
+	}
+	The second definition of x reaches the code *before* it.
+	Therefore we must go over the loop body a second time with known reaching definitions and add the necessary usedefs.*/
+static void loop_second_pass(AST *a) {
+	if(a->nodeKind == AST_CHUNK) {
+		for(AST *s = a->chunk.statementFirst; s; s = s->statement.next) {
+			loop_second_pass(s);
+		}
+	} else if(a->nodeKind == AST_STMT_IF) {
+		loop_second_pass(a->stmtIf.expression);
+		loop_second_pass(a->stmtIf.then);
+	} else if(a->nodeKind == AST_STMT_LOOP) {
+		loop_second_pass(a->stmtLoop.body);
+	} else if(a->nodeKind == AST_STMT_ASSIGN) {
+		loop_second_pass(a->stmtAssign.what);
+		loop_second_pass(a->stmtAssign.to);
+		
+		/* TODO: Per-variable flag.to cease additional usedefs after assignment?
+			It is okay to have too many usedefs, so this isn't high priority.*/
+	} else if(a->nodeKind == AST_STMT_EXPR) {
+		loop_second_pass(a->stmtExpr.expr);
+	} else if(a->nodeKind == AST_EXPR_VAR) {
+		UseDef *udPrev = NULL;
+		UseDef *ud = a->exprVar.thing->data.var.usedefFirst;
+		while(ud && ud->use != a) {
+			udPrev = ud;
+			ud = ud->next;
+		}
+		
+		if(ud) {
+			ReachingDefs *defs = a->exprVar.thing->data.var.reachingDefs;
+			while(defs) {
+				for(size_t i = 0; i < defs->defCount; i++) {
+					UseDef *newud = calloc(1, sizeof(*newud));
+					memcpy(newud, ud, sizeof(*ud));
+					newud->def = defs->defs[i];
+					
+					udPrev->next = newud;
+					newud->next = ud;
+					ud = newud;
+				}
+				
+				if(defs->excludeParent) {
+					break;
+				}
+				
+				defs = defs->parent;
+			}
+		}
+	} else if(a->nodeKind == AST_EXPR_BINARY_OP) {
+		loop_second_pass(a->exprBinOp.operands[0]);
+		loop_second_pass(a->exprBinOp.operands[1]);
+	} else if(a->nodeKind == AST_EXPR_UNARY_OP) {
+		loop_second_pass(a->exprUnOp.operand);
+	} else if(a->nodeKind == AST_EXPR_CAST) {
+		loop_second_pass(a->exprCast.what);
+	} else if(a->nodeKind == AST_EXPR_CALL) {
+		loop_second_pass(a->exprCall.what);
+		
+		size_t argCount = a->exprCall.what->expression.type->function.argCount;
+		for(size_t i = 0; i < argCount; i++) {
+			loop_second_pass(a->exprCall.args[i]);
+		}
+	}
+}
+
 ASTChunk *nct_parse_chunk(Parser*, int, int);
 void nct_parse_statement(Parser *P) {
 	if(maybe(P, TOKEN_IF)) {
@@ -657,10 +805,31 @@ void nct_parse_statement(Parser *P) {
 		ret->nodeKind = AST_STMT_LOOP;
 		ret->next = NULL;
 		
+		int isFirstLoop = P->loopScope == NULL;
+		
+		if(isFirstLoop) {
+			P->loopScope = P->scope;
+		}
+		
 		expect(P, TOKEN_SQUIGGLY_L);
 		ret->body = (AST*) nct_parse_chunk(P, 0, 1);
 		expect(P, TOKEN_SQUIGGLY_R);
 		
+		if(isFirstLoop) {
+			P->loopScope = NULL;
+			
+			for(size_t i = 0; i < P->guardedVarCount; i++) {
+				ASTExprVar *ev = P->guardedVars[i];
+				
+				newusedef(P, ev->thing, ev);
+			}
+			P->guardedVarCount = 0;
+			free(P->guardedVars);
+			P->guardedVars = NULL;
+		}
+		
+		loop_second_pass(ret->body);
+		
 		pushstat(P, ret);
 		return;
 	} else if(maybe(P, TOKEN_BREAK)) {
@@ -749,7 +918,7 @@ void nct_parse_statement(Parser *P) {
 		ret->nodeKind = AST_STMT_ASSIGN;
 		ret->next = NULL;
  		ret->what = e;
-		ret->to = nct_parse_expression(P, 0);//nct_cast_expr(nct_parse_expression(P, 0), ret->what->expression.type);
+		ret->to = nct_cast_expr(nct_parse_expression(P, 0), ret->what->expression.type);
 		
 		if(ret->what->nodeKind == AST_EXPR_VAR) {
 			reachingdefs_set(ret->what->exprVar.thing->data.var.reachingDefs, (AST*) ret);
@@ -773,9 +942,6 @@ void nct_parse_statement(Parser *P) {
 }
 
 ASTChunk *nct_parse_chunk(Parser *P, int isTopLevel, int varPrioritize) {
-	if(P->scope) {
-	}
-	
 	AST *ret = malloc(sizeof(ASTChunk));
 	ret->nodeKind = AST_CHUNK;
 	ret->chunk.statementFirst = ret->chunk.statementLast = NULL;
@@ -851,6 +1017,7 @@ ASTChunk *nct_parse_chunk(Parser *P, int isTopLevel, int varPrioritize) {
 	for(size_t i = 0; i < P->scope->count; i++) {
 		if(P->scope->data[i]->kind == VARTABLEENTRY_VAR) {
 			P->topLevel->vars[P->topLevel->varCount++] = P->scope->data[i];
+			P->scope->data[i]->owner = P->topLevel;
 		}
 	}
 	

src/types.c

@@ -22,7 +22,7 @@ Type *primitive_parse(const char *src) {
 	
 	TypePrimitive *ret = malloc(sizeof(*ret));
 	ret->type = TYPE_TYPE_PRIMITIVE;
-	ret->src = src;
+	ret->src = strdup(src);
 	
 	if(*src == 'n') {
 		src++;

src/types.h

@@ -62,6 +62,7 @@ typedef union Type {
 extern Type TYPE_ERROR;
 
 Type *primitive_parse(const char*);
+Type *primitive_make(uint16_t width);
 
 size_t type_size(Type*);
 int type_equal(Type*, Type*);

src/vartable.c

@@ -26,6 +26,7 @@ void reachingdefs_set(struct ReachingDefs *this, union AST *def) {
 	this->defCount = 1;
 	this->defs = realloc(this->defs, sizeof(*this->defs) * this->defCount);
 	this->defs[0] = def;
+	this->excludeParent = 1;
 }
 
 VarTable *vartable_new(VarTable *parent) {
@@ -64,6 +65,7 @@ VarTableEntry *vartable_set(VarTable *this, const char *name, VarTableEntry *e)
 	this->data[this->count] = e;
 	this->count++;
 	if(e->kind == VARTABLEENTRY_VAR) e->data.var.name = name;
+	e->owner = this;
 	return e;
 }
 

src/vartable.h

@@ -20,15 +20,19 @@ typedef struct ReachingDefs {
 	size_t defCount;
 	union AST **defs;
 	
+	int excludeParent;
 	struct ReachingDefs *parent;
 } ReachingDefs;
 struct ReachingDefs *reachingdefs_push(struct ReachingDefs*);
 struct ReachingDefs *reachingdefs_coalesce(struct ReachingDefs*);
 void reachingdefs_set(struct ReachingDefs*, union AST*);
 
+struct VarTable;
 typedef struct VarTableEntry {
 	Type *type;
 	
+	struct VarTable *owner;
+	
 	VarTableEntryKind kind;
 	struct {
 		union {

src/x86.h

@@ -0,0 +1,35 @@
+#pragma once
+
+// Can expression be expressed as a single x86 operand?
+#define XOP_NOT_XOP 0
+#define XOP_NOT_MEM 1
+#define XOP_MEM 2
+static inline int is_xop(AST *e) {
+	if(e->nodeKind == AST_EXPR_PRIMITIVE) {
+		return XOP_NOT_MEM;
+	} else if(e->nodeKind == AST_EXPR_VAR) {
+		return e->exprVar.thing->kind == VARTABLEENTRY_VAR ? XOP_NOT_MEM : XOP_MEM;
+	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF && e->exprUnOp.operand->nodeKind == AST_EXPR_BINARY_OP && e->exprUnOp.operand->exprBinOp.operator == BINOP_ADD && e->exprUnOp.operand->exprBinOp.operands[0]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprBinOp.operands[0]->exprVar.thing->kind == VARTABLEENTRY_VAR && e->exprUnOp.operand->exprBinOp.operands[1]->exprVar.thing->kind == VARTABLEENTRY_VAR) {
+		return XOP_MEM;
+	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_REF && e->exprUnOp.operand->nodeKind == AST_EXPR_VAR && e->exprUnOp.operand->exprVar.thing->kind == VARTABLEENTRY_SYMBOL) {
+		return XOP_NOT_MEM;
+	} else if(e->nodeKind == AST_EXPR_UNARY_OP && e->exprUnOp.operator == UNOP_DEREF) {
+		AST *c = e->exprUnOp.operand;
+		
+		if(c->nodeKind == AST_EXPR_VAR && c->exprVar.thing->kind == VARTABLEENTRY_VAR) {
+			return XOP_MEM;
+		} else if(c->nodeKind == AST_EXPR_BINARY_OP && c->exprBinOp.operator == BINOP_ADD && c->exprBinOp.operands[0]->nodeKind == AST_EXPR_UNARY_OP && c->exprBinOp.operands[0]->exprUnOp.operator == UNOP_REF && c->exprBinOp.operands[0]->exprUnOp.operand->nodeKind == AST_EXPR_VAR) {
+			if(c->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR) {
+				return XOP_MEM;
+			} else if(c->exprBinOp.operands[1]->nodeKind == AST_EXPR_BINARY_OP && c->exprBinOp.operands[1]->exprBinOp.operator == BINOP_MUL && c->exprBinOp.operands[1]->exprBinOp.operands[0]->nodeKind == AST_EXPR_PRIMITIVE && c->exprBinOp.operands[1]->exprBinOp.operands[1]->nodeKind == AST_EXPR_VAR) {
+				int scale = c->exprBinOp.operands[1]->exprBinOp.operands[0]->exprPrim.val;
+				
+				if(scale == 1 || scale == 2 || scale == 4 || scale == 8) {
+					return XOP_MEM;
+				}
+			}
+		}
+	}
+	
+	return XOP_NOT_XOP;
+}

tests/bf.nct

@@ -30,12 +30,10 @@ loop {
 		data[dataPtr] = data[dataPtr] - 1;
 	}
 	if(code[codePtr] == 46) {
-		u32 z = &data + dataPtr;
+		write(1, &data + dataPtr, 1);
-		write(1, z, 1);
 	}
 	if(code[codePtr] == 44) {
-		u32 z = &data + dataPtr;
+		read(0, &data + dataPtr, 1);
-		read(0, z, 1);
 	}
 	if(code[codePtr] == 91) {
 		if(data[dataPtr] == 0) {
@@ -75,7 +73,3 @@ loop {
 	
 	codePtr = codePtr + 1;
 }
-
-codePtr;
-dataPtr;
-stckPtr;

tests/bit-rounding.nct

@@ -1,2 +1,6 @@
 u32 x: 123;
 u33 y: 5;
+
+u3 *o = 5000;
+u3 z = *o;
+u3 p = *(o + z);

tests/if.nct

@@ -2,7 +2,8 @@ u16 x: 5;
 loop {
 	u16* y = 257;
 	u9 w = -4;
-	u4 z = 3 + *y;
+	u16 p = *y;
+	u4 z = p + 3;
 	u2 o = -w;
 	
 	if(x != 0) {

tests/loopregalloc.nct

@@ -0,0 +1,9 @@
+u8 a;
+
+loop {
+	a = 3;
+	
+	u8 b = 1;
+	
+	u8 c = 2;
+}

tests/scoping.nct

@@ -1,5 +1,5 @@
 u8 a = 5;
-if(a) {
+if(a != 0) {
 	u8 a = 10; /* Should not cause scoping errors. */
 }
 u8 b = 15; /* `a` in the if statement scope should be free'd. */