From 7e901299bf55e14bd1482f3a96b2ff5b790665de Mon Sep 17 00:00:00 2001
From: grischka <grischka>
Date: Tue, 21 Jan 2020 14:23:57 +0100
Subject: [PATCH] Rework expr_infix
- revert const-folding in gvtst() and put it back into
expr_landor(). Although it did make sense, one reason
not to do it is __builtin_constant_p() which may return
true when it shouldn't because of nocode_wanted, see test.
- tccgen_init() can do init_prec(), also for tcc -E.
- for nostalgic reasons, keep the original expression parser
functions in the source.
- Makefile: remove stale stuff
---
Makefile | 13 +--
tcc.h | 1 -
tccgen.c | 254 +++++++++++++++++++++++++++++++++++-------------
tccpp.c | 2 -
tests/tcctest.c | 3 +
5 files changed, 191 insertions(+), 82 deletions(-)
diff --git a/Makefile b/Makefile
index 2c048d01..9e973308 100644
--- a/Makefile
+++ b/Makefile
@@ -238,20 +238,13 @@ XTCC ?= ./tcc$(EXESUF)
# TinyCC runtime libraries
libtcc1.a : tcc$(EXESUF) FORCE
- @$(MAKE) -C lib DEFINES='$(DEF-$T)'
+ @$(MAKE) -C lib
# Cross libtcc1.a
%-libtcc1.a : %-tcc$(EXESUF) FORCE
- @$(MAKE) -C lib DEFINES='$(DEF-$*)' CROSS_TARGET=$*
+ @$(MAKE) -C lib CROSS_TARGET=$*
-# TinyCC runtime libraries
-libtccb1.a : libtcc1.a
-
-# Cross libtcc1.a
-%-libtccb1.a : %-tcc$(EXESUF) FORCE
- @$(MAKE) -C lib DEFINES='$(DEF-$*)' CROSS_TARGET=$*
-
-.PRECIOUS: %-libtcc1.a %-libtccb1.a
+.PRECIOUS: %-libtcc1.a
FORCE:
# --------------------------------------------------------------------------
diff --git a/tcc.h b/tcc.h
index 558f87f7..82238ce0 100644
--- a/tcc.h
+++ b/tcc.h
@@ -1434,7 +1434,6 @@ ST_FUNC void parse_mult_str (CString *astr, const char *msg);
ST_FUNC void parse_asm_str(CString *astr);
ST_FUNC void indir(void);
ST_FUNC void unary(void);
-ST_FUNC void init_prec(void);
ST_FUNC void gexpr(void);
ST_FUNC int expr_const(void);
#if defined CONFIG_TCC_BCHECK || defined TCC_TARGET_C67
diff --git a/tccgen.c b/tccgen.c
index 131f0818..6fd24760 100644
--- a/tccgen.c
+++ b/tccgen.c
@@ -67,7 +67,7 @@ static int gind(void) { CODE_ON(); return ind; }
/* Set 'nocode_wanted' after unconditional jumps */
static void gjmp_addr_acs(int t) { gjmp_addr(t); CODE_OFF(); }
-static int gjmp_acs(int t) { if (!nocode_wanted) {t = gjmp(t); CODE_OFF(); } return t; }
+static int gjmp_acs(int t) { t = gjmp(t); CODE_OFF(); return t; }
/* These are #undef'd at the end of this file */
#define gjmp_addr gjmp_addr_acs
@@ -122,6 +122,11 @@ static struct scope {
Sym *lstk, *llstk;
} *cur_scope, *loop_scope, *root_scope;
+/********************************************************/
+#if 1
+#define precedence_parser
+static void init_prec(void);
+#endif
/********************************************************/
#ifndef CONFIG_TCC_ASM
ST_FUNC void asm_instr(void)
@@ -135,7 +140,6 @@ ST_FUNC void asm_global_instr(void)
#endif
/* ------------------------------------------------------------------------- */
-
static void gen_cast(CType *type);
static void gen_cast_s(int t);
static inline CType *pointed_type(CType *type);
@@ -455,6 +459,9 @@ ST_FUNC void tccgen_init(TCCState *s1)
func_old_type.ref = sym_push(SYM_FIELD, &int_type, 0, 0);
func_old_type.ref->f.func_call = FUNC_CDECL;
func_old_type.ref->f.func_type = FUNC_OLD;
+#ifdef precedence_parser
+ init_prec();
+#endif
}
ST_FUNC int tccgen_compile(TCCState *s1)
@@ -877,7 +884,7 @@ static void vcheck_cmp(void)
again, so that the VT_CMP/VT_JMP value will be in vtop
when code is unsuppressed again. */
- if (vtop->r == VT_CMP && !nocode_wanted && vtop->cmp_op > 1)
+ if (vtop->r == VT_CMP && !nocode_wanted)
gv(RC_INT);
}
@@ -1040,14 +1047,11 @@ ST_FUNC void vset_VT_CMP(int op)
static void vset_VT_JMP(void)
{
int op = vtop->cmp_op;
+
if (vtop->jtrue || vtop->jfalse) {
/* we need to jump to 'mov $0,%R' or 'mov $1,%R' */
int inv = op & (op < 2); /* small optimization */
- int t = gvtst(inv, 0);
- if (t) /* in case gvtst only needed to do a gsym */
- vseti(VT_JMP+inv, t);
- else
- vpushi(inv);
+ vseti(VT_JMP+inv, gvtst(inv, 0));
} else {
/* otherwise convert flags (rsp. 0/1) to register */
vtop->c.i = op;
@@ -1060,18 +1064,14 @@ static void vset_VT_JMP(void)
static void gvtst_set(int inv, int t)
{
int *p;
+
if (vtop->r != VT_CMP) {
vpushi(0);
gen_op(TOK_NE);
- if (vtop->r == VT_CMP) /* must be VT_CONST otherwise */
- ;
- else if (vtop->r == VT_CONST) {
- if (!t)
- return;
+ if (vtop->r != VT_CMP) /* must be VT_CONST then */
vset_VT_CMP(vtop->c.i != 0);
- } else
- tcc_error("ICE");
}
+
p = inv ? &vtop->jfalse : &vtop->jtrue;
*p = gjmp_append(*p, t);
}
@@ -1082,20 +1082,16 @@ static void gvtst_set(int inv, int t)
static int gvtst(int inv, int t)
{
int op, x, u;
+
gvtst_set(inv, t);
- if (vtop->r != VT_CMP) {
- t = u = x = 0;
- op = vtop->c.i;
- } else {
- t = vtop->jtrue, u = vtop->jfalse;
- if (inv)
- x = u, u = t, t = x;
- op = vtop->cmp_op;
- }
+ t = vtop->jtrue, u = vtop->jfalse;
+ if (inv)
+ x = u, u = t, t = x;
+ op = vtop->cmp_op;
/* jump to the wanted target */
if (op > 1)
- t = gjmp_cond(op ^ inv, t), op = inv;//, op = 1;
+ t = gjmp_cond(op ^ inv, t);
else if (op != inv)
t = gjmp(t);
/* resolve complementary jumps to here */
@@ -5690,22 +5686,120 @@ special_math_val:
}
}
-/* Assuming vtop is a value used in a conditional context
- (i.e. compared with zero) return 0 if it's false, 1 if
- true and -1 if it can't be statically determined. */
-static int condition_3way(void)
+#ifndef precedence_parser /* original top-down parser */
+
+static void expr_prod(void)
{
- int c = -1;
- if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST &&
- (!(vtop->r & VT_SYM) || !vtop->sym->a.weak)) {
- vdup();
- gen_cast_s(VT_BOOL);
- c = vtop->c.i;
- vpop();
+ int t;
+
+ unary();
+ while ((t = tok) == '*' || t == '/' || t == '%') {
+ next();
+ unary();
+ gen_op(t);
}
- return c;
}
+static void expr_sum(void)
+{
+ int t;
+
+ expr_prod();
+ while ((t = tok) == '+' || t == '-') {
+ next();
+ expr_prod();
+ gen_op(t);
+ }
+}
+
+static void expr_shift(void)
+{
+ int t;
+
+ expr_sum();
+ while ((t = tok) == TOK_SHL || t == TOK_SAR) {
+ next();
+ expr_sum();
+ gen_op(t);
+ }
+}
+
+static void expr_cmp(void)
+{
+ int t;
+
+ expr_shift();
+ while (((t = tok) >= TOK_ULE && t <= TOK_GT) ||
+ t == TOK_ULT || t == TOK_UGE) {
+ next();
+ expr_shift();
+ gen_op(t);
+ }
+}
+
+static void expr_cmpeq(void)
+{
+ int t;
+
+ expr_cmp();
+ while ((t = tok) == TOK_EQ || t == TOK_NE) {
+ next();
+ expr_cmp();
+ gen_op(t);
+ }
+}
+
+static void expr_and(void)
+{
+ expr_cmpeq();
+ while (tok == '&') {
+ next();
+ expr_cmpeq();
+ gen_op('&');
+ }
+}
+
+static void expr_xor(void)
+{
+ expr_and();
+ while (tok == '^') {
+ next();
+ expr_and();
+ gen_op('^');
+ }
+}
+
+static void expr_or(void)
+{
+ expr_xor();
+ while (tok == '|') {
+ next();
+ expr_xor();
+ gen_op('|');
+ }
+}
+
+static void expr_landor(int op);
+
+static void expr_land(void)
+{
+ expr_or();
+ if (tok == TOK_LAND)
+ expr_landor(tok);
+}
+
+static void expr_lor(void)
+{
+ expr_land();
+ if (tok == TOK_LOR)
+ expr_landor(tok);
+}
+
+# define expr_landor_next(op) op == TOK_LAND ? expr_or() : expr_land()
+#else /* defined precedence_parser */
+# define expr_landor_next(op) unary(), expr_infix(precedence(op) + 1)
+# define expr_lor() unary(), expr_infix(1)
+
static int precedence(int tok)
{
switch (tok) {
@@ -5725,44 +5819,23 @@ static int precedence(int tok)
return 0;
}
}
-
static unsigned char prec[256];
-ST_FUNC void init_prec(void)
+static void init_prec(void)
{
int i;
for (i = 0; i < 256; i++)
prec[i] = precedence(i);
}
-
#define precedence(i) ((unsigned)i < 256 ? prec[i] : 0)
-static void expr_infix(int p);
-static void expr_landor(int p, int e_op, int i)
-{
- int t = 0, f = 0;
- save_regs(1);
- do {
- if (!f && condition_3way() == !i)
- nocode_wanted++, f = 1;
- t = gvtst(i, t);
- next();
- unary();
- expr_infix(p);
- } while (tok == e_op);
- if (f) {
- vpop();
- vpushi(i ^ f);
- }
- gvtst_set(i, t);
- nocode_wanted -= f;
-}
+static void expr_landor(int op);
static void expr_infix(int p)
{
int t = tok, p2;
while ((p2 = precedence(t)) >= p) {
if (t == TOK_LOR || t == TOK_LAND) {
- expr_landor(p2 + 1, t, t == TOK_LAND);
+ expr_landor(t);
} else {
next();
unary();
@@ -5773,6 +5846,51 @@ static void expr_infix(int p)
t = tok;
}
}
+#endif
+
+/* Assuming vtop is a value used in a conditional context
+ (i.e. compared with zero) return 0 if it's false, 1 if
+ true and -1 if it can't be statically determined. */
+static int condition_3way(void)
+{
+ int c = -1;
+ if ((vtop->r & (VT_VALMASK | VT_LVAL)) == VT_CONST &&
+ (!(vtop->r & VT_SYM) || !vtop->sym->a.weak)) {
+ vdup();
+ gen_cast_s(VT_BOOL);
+ c = vtop->c.i;
+ vpop();
+ }
+ return c;
+}
+
+static void expr_landor(int op)
+{
+ int t = 0, cc = 1, f = 0, i = op == TOK_LAND, c;
+ for(;;) {
+ c = f ? i : condition_3way();
+ if (c < 0)
+ save_regs(1), cc = 0;
+ else if (c != i)
+ nocode_wanted++, f = 1;
+ if (tok != op)
+ break;
+ if (c < 0)
+ t = gvtst(i, t);
+ else
+ vpop();
+ next();
+ expr_landor_next(op);
+ }
+ if (cc || f) {
+ vpop();
+ vpushi(i ^ f);
+ gsym(t);
+ nocode_wanted -= f;
+ } else {
+ gvtst_set(i, t);
+ }
+}
static int is_cond_bool(SValue *sv)
{
@@ -5791,11 +5909,11 @@ static void expr_cond(void)
CType type, type1, type2;
int ncw_prev;
- unary();
- expr_infix(1);
+ expr_lor();
if (tok == '?') {
next();
c = condition_3way();
+ ncw_prev = nocode_wanted;
g = (tok == ':' && gnu_ext);
tt = 0;
if (!g) {
@@ -5813,7 +5931,6 @@ static void expr_cond(void)
tt = gvtst(0, 0);
}
- ncw_prev = nocode_wanted;
if (1) {
if (c == 0)
nocode_wanted++;
@@ -6013,12 +6130,11 @@ static void expr_eq(void)
int t;
expr_cond();
- if (tok == '=' ||
- (tok >= TOK_A_MOD && tok <= TOK_A_DIV) ||
- tok == TOK_A_XOR || tok == TOK_A_OR ||
- tok == TOK_A_SHL || tok == TOK_A_SAR) {
+ if ((t = tok) == '='
+ || (t >= TOK_A_MOD && t <= TOK_A_DIV)
+ || t == TOK_A_XOR || t == TOK_A_OR
+ || t == TOK_A_SHL || t == TOK_A_SAR) {
test_lvalue();
- t = tok;
next();
if (t == '=') {
expr_eq();
diff --git a/tccpp.c b/tccpp.c
index 99bd87be..e70c2bb2 100644
--- a/tccpp.c
+++ b/tccpp.c
@@ -3679,8 +3679,6 @@ ST_FUNC void tccpp_new(TCCState *s)
define_push(TOK___DATE__, MACRO_OBJ, NULL, NULL);
define_push(TOK___TIME__, MACRO_OBJ, NULL, NULL);
define_push(TOK___COUNTER__, MACRO_OBJ, NULL, NULL);
-
- init_prec();
}
ST_FUNC void tccpp_delete(TCCState *s)
diff --git a/tests/tcctest.c b/tests/tcctest.c
index dbf4b753..059d0f7b 100644
--- a/tests/tcctest.c
+++ b/tests/tcctest.c
@@ -3736,6 +3736,9 @@ void builtin_test(void)
printf("res = %d\n", __builtin_constant_p(&constant_p_var));
printf("res = %d\n", __builtin_constant_p(constant_p_var));
printf("res = %d\n", __builtin_constant_p(100000 / constant_p_var));
+ printf("res = %d\n", __builtin_constant_p(i && 0));
+ printf("res = %d\n", __builtin_constant_p(i && 1));
+ printf("res = %d\n", __builtin_constant_p(i && 0 ? i : 34));
s = 1;
ll = 2;
i = __builtin_choose_expr (1 != 0, ll, s);