shithub: scc

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Fix switch emittion

Switch was broken in different ways. Case and default statements
were not composed of label part and statement part, but only
of the label part. This was not important except in this case:

	switch (x)
	case 1:
		switch (x)
		case 1:
			return 0;

The output format for switch is also modified.

--- a/cc1/cc1.h

+++ b/cc1/cc1.h

@@ -82,6 +82,9 @@

 struct caselist {

 	short nr;

 	Symbol *deflabel;

+	Symbol *ltable;

+	Symbol *lbreak;

+	Node *expr;

 	struct scase *head;

 };

@@ -282,6 +285,7 @@

 	ORET,

 	ODECL,

 	OSWITCH,

+	OSWITCHT,

 	OAND,

 	OOR,

 	OEQ,

--- a/cc1/code.c

+++ b/cc1/code.c

@@ -7,7 +7,7 @@

 #include "../inc/cc.h"

 #include "cc1.h"

-static void emitbin(unsigned, void *),

+static void emitbin(unsigned, void *), emitswitcht(unsigned, void *),

             emitcast(unsigned, void *), emitswitch(unsigned, void *),

             emitsym(unsigned, void *),

             emitexp(unsigned, void *),

@@ -55,7 +55,7 @@

 	[OCOMMA] = ",",

 	[OLABEL] = "L%d\n",

 	[ODEFAULT] = "\tf\tL%d\n",

-	[OCASE] = "\tw\tL%d",

+	[OCASE] = "\tv\tL%d",

 	[OJUMP] = "\tj\tL%d\n",

 	[OBRANCH] = "\tj\tL%d",

 	[OEFUN] = "}",

@@ -121,6 +121,7 @@

 	[ORET] = emitret,

 	[ODECL] = emitdcl,

 	[OSWITCH] = emitswitch,

+	[OSWITCHT] = emitswitcht,

 	[OPAR] = emitbin,

 	[OCALL] = emitbin

 };

@@ -368,7 +369,25 @@

 {

 	Caselist *lcase = arg;

-	printf("\teI\t#%0x", lcase->nr);

+	printf("\ts\tL%u", lcase->ltable->id);

+	emitexp(OEXPR, lcase->expr);

+}

+

+static void

+emitswitcht(unsigned op, void *arg)

+{

+	Caselist *lcase = arg;

+	struct scase *p, *next;

+

+	printf("\tt\t#%0x\n", lcase->nr);

+	for (p = lcase->head; p; p = next) {

+		emitsymid(OCASE, p->label);

+		emitexp(OEXPR, p->expr);

+		next = p->next;

+		free(p);

+	}

+	if (lcase->deflabel)

+		emitsymid(ODEFAULT, lcase->deflabel);

 }

 Node *

--- a/cc1/stmt.c

+++ b/cc1/stmt.c

@@ -189,14 +189,13 @@

 Switch(Symbol *lbreak, Symbol *lcont, Caselist *lswitch)

 {

 	Caselist lcase = {.nr = 0, .head = NULL, .deflabel = NULL};

-	struct scase *p, *next;

 	Node *cond;

-	Symbol *lcond;

-	void free(void *ptr);

 	expect(SWITCH);

 	expect ('(');

-	cond = expr();

+	cond = eval(expr());

+	/* TODO: why can I not call directly to convert here? */

+

 	switch (BTYPE(cond)) {

 	case INT:

 	case ENUM:

@@ -207,22 +206,16 @@

 	}

 	expect (')');

-	lbreak = newsym(NS_LABEL);

-	lcond = newsym(NS_LABEL);

-	emit(OJUMP, lcond);

-	stmt(lbreak, lcont, &lcase);

-	emit(OLABEL, lcond);

+	lcase.expr = cond;

+	lcase.lbreak = newsym(NS_LABEL);

+	lcase.ltable = newsym(NS_LABEL);

+

 	emit(OSWITCH, &lcase);

-	emit(OEXPR, cond);

-	for (p = lcase.head; p; p = next) {

-		emit(OCASE, p->label);

-		emit(OEXPR, p->expr);

-		next = p->next;

-		free(p);

-	}

-	if (lcase.deflabel)

-		emit(ODEFAULT, lcase.deflabel);

-	emit(OLABEL, lbreak);

+	stmt(lbreak, lcont, &lcase);

+	emit(OJUMP, lcase.lbreak);

+	emit(OLABEL, lcase.ltable);

+	emit(OSWITCHT, &lcase);

+	emit(OLABEL, lcase.lbreak);

 }

 static void

@@ -243,6 +236,7 @@

 	emit(OLABEL, pcase->label = newsym(NS_LABEL));

 	lswitch->head = pcase;

 	++lswitch->nr;

+	stmt(lbreak, lcont, lswitch);

 }

 static void

@@ -254,6 +248,8 @@

 	expect(':');

 	emit(OLABEL, ldefault);

 	lswitch->deflabel = ldefault;

+	++lswitch->nr;

+	stmt(lbreak, lcont, lswitch);

 }

 static void

--- /dev/null

+++ b/cc1/tests/test012.c

@@ -1,0 +1,111 @@

+/*

+name: TEST012

+description: Basic switch test

+output:

+F1

+G1	F1	main

+{

+-

+A2	I	x

+	A2	#I0	:I

+	s	L4	A2

+L5

+	j	L3

+L4

+	t	#1

+	v	L5	#I0

+L3

+	s	L7	A2

+L8

+	s	L10	A2

+L11

+	j	L12

+L13

+	yI	#I1

+	j	L9

+L10

+	t	#2

+	v	L11	#I0

+	f	L13

+L9

+	j	L6

+L7

+	t	#1

+	v	L8	#I0

+L6

+	yI	#I2

+L12

+	s	L15	A2

+L16

+	yI	#I3

+	j	L14

+L15

+	t	#1

+	v	L16	#I1

+L14

+	s	L18	A2

+	A2	#I2	:I

+L19

+L20

+	yI	#I4

+	j	L17

+L18

+	t	#1

+	v	L20	#I1

+L17

+	s	L22	A2

+L23

+	yI	A2

+L24

+	yI	#I1

+L25

+	yI	#I1

+	j	L21

+L22

+	t	#3

+	v	L24	#I1

+	v	L23	#I0

+	f	L25

+L21

+}

+*/

+

+

+

+int

+main()

+{

+	int x;

+

+	x = 0;

+	switch(x)

+	case 0:

+		;

+	switch(x)

+	case 0:

+		switch(x) {

+		case 0:

+			goto next;

+		default:

+			return 1;

+		}

+	return 2;

+	next:

+	switch(x)

+	case 1:

+		return 3;

+	switch(x) {

+		x = 1 + 1;

+		foo:

+	case 1:

+		return 4;

+	}

+	switch(x) {

+	case 0:

+		return x;

+	case 1:

+		return 1;

+	default:

+		return 1;

+	}

+}