From 7ca8105a2ea7b6a0d7b55b59d273ccd271c35268 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Mon, 27 Mar 2023 16:29:39 -0300 Subject: [PATCH] More orderliness in casts of enumerations --- lcode.c | 55 +++++++++++++++++++++++++++++++++++++++++-------------- ldebug.c | 29 ++++++++++++++++------------- 2 files changed, 57 insertions(+), 27 deletions(-) diff --git a/lcode.c b/lcode.c index 236ce05c..1a371ca9 100644 --- a/lcode.c +++ b/lcode.c @@ -1351,6 +1351,35 @@ static int constfolding (FuncState *fs, int op, expdesc *e1, } +/* +** Convert a BinOpr to an OpCode (ORDER OPR - ORDER OP) +*/ +l_sinline OpCode binopr2op (BinOpr opr, BinOpr baser, OpCode base) { + lua_assert(baser <= opr && + ((baser == OPR_ADD && opr <= OPR_SHR) || + (baser == OPR_LT && opr <= OPR_LE))); + return cast(OpCode, (cast_int(opr) - cast_int(baser)) + cast_int(base)); +} + + +/* +** Convert a UnOpr to an OpCode (ORDER OPR - ORDER OP) +*/ +l_sinline OpCode unopr2op (UnOpr opr) { + return cast(OpCode, (cast_int(opr) - cast_int(OPR_MINUS)) + + cast_int(OP_UNM)); +} + + +/* +** Convert a BinOpr to a tag method (ORDER OPR - ORDER TM) +*/ +l_sinline TMS binopr2TM (BinOpr opr) { + lua_assert(OPR_ADD <= opr && opr <= OPR_SHR); + return cast(TMS, (cast_int(opr) - cast_int(OPR_ADD)) + cast_int(TM_ADD)); +} + + /* ** Emit code for unary expressions that "produce values" ** (everything but 'not'). @@ -1391,14 +1420,13 @@ static void finishbinexpval (FuncState *fs, expdesc *e1, expdesc *e2, */ static void codebinexpval (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2, int line) { - OpCode op = cast(OpCode, opr + OP_ADD); + OpCode op = binopr2op(opr, OPR_ADD, OP_ADD); int v2 = luaK_exp2anyreg(fs, e2); /* make sure 'e2' is in a register */ /* 'e1' must be already in a register or it is a constant */ lua_assert((VNIL <= e1->k && e1->k <= VKSTR) || e1->k == VNONRELOC || e1->k == VRELOC); lua_assert(OP_ADD <= op && op <= OP_SHR); - finishbinexpval(fs, e1, e2, op, v2, 0, line, OP_MMBIN, - cast(TMS, opr + TM_ADD)); + finishbinexpval(fs, e1, e2, op, v2, 0, line, OP_MMBIN, binopr2TM(opr)); } @@ -1419,9 +1447,9 @@ static void codebini (FuncState *fs, OpCode op, */ static void codebinK (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2, int flip, int line) { - TMS event = cast(TMS, opr + TM_ADD); + TMS event = binopr2TM(opr); int v2 = e2->u.info; /* K index */ - OpCode op = cast(OpCode, opr + OP_ADDK); + OpCode op = binopr2op(opr, OPR_ADD, OP_ADDK); finishbinexpval(fs, e1, e2, op, v2, flip, line, OP_MMBINK, event); } @@ -1527,18 +1555,18 @@ static void codeorder (FuncState *fs, BinOpr opr, expdesc *e1, expdesc *e2) { /* use immediate operand */ r1 = luaK_exp2anyreg(fs, e1); r2 = im; - op = cast(OpCode, (opr - OPR_LT) + OP_LTI); + op = binopr2op(opr, OPR_LT, OP_LTI); } else if (isSCnumber(e1, &im, &isfloat)) { /* transform (A < B) to (B > A) and (A <= B) to (B >= A) */ r1 = luaK_exp2anyreg(fs, e2); r2 = im; - op = cast(OpCode, (opr - OPR_LT) + OP_GTI); + op = binopr2op(opr, OPR_LT, OP_GTI); } else { /* regular case, compare two registers */ r1 = luaK_exp2anyreg(fs, e1); r2 = luaK_exp2anyreg(fs, e2); - op = cast(OpCode, (opr - OPR_EQ) + OP_EQ); + op = binopr2op(opr, OPR_LT, OP_LT); } freeexps(fs, e1, e2); e1->u.info = condjump(fs, op, r1, r2, isfloat, 1); @@ -1590,7 +1618,7 @@ void luaK_prefix (FuncState *fs, UnOpr opr, expdesc *e, int line) { break; /* else */ /* FALLTHROUGH */ case OPR_LEN: - codeunexpval(fs, cast(OpCode, opr + OP_UNM), e, line); + codeunexpval(fs, unopr2op(opr), e, line); break; case OPR_NOT: codenot(fs, e); break; default: lua_assert(0); @@ -1734,14 +1762,13 @@ void luaK_posfix (FuncState *fs, BinOpr opr, codeeq(fs, opr, e1, e2); break; } - case OPR_LT: case OPR_LE: { - codeorder(fs, opr, e1, e2); - break; - } case OPR_GT: case OPR_GE: { /* '(a > b)' <=> '(b < a)'; '(a >= b)' <=> '(b <= a)' */ swapexps(e1, e2); - codeorder(fs, (opr - OPR_NE) + OPR_EQ, e1, e2); + opr = cast(BinOpr, (opr - OPR_GT) + OPR_LT); + } /* FALLTHROUGH */ + case OPR_LT: case OPR_LE: { + codeorder(fs, opr, e1, e2); break; } default: lua_assert(0); diff --git a/ldebug.c b/ldebug.c index 3fae5cf2..7a61a780 100644 --- a/ldebug.c +++ b/ldebug.c @@ -656,18 +656,19 @@ static const char *funcnamefromcall (lua_State *L, CallInfo *ci, /* -** Check whether pointer 'o' points to some value in the stack -** frame of the current function. Because 'o' may not point to a -** value in this stack, we cannot compare it with the region -** boundaries (undefined behaviour in ISO C). +** Check whether pointer 'o' points to some value in the stack frame of +** the current function and, if so, returns its index. Because 'o' may +** not point to a value in this stack, we cannot compare it with the +** region boundaries (undefined behaviour in ISO C). */ -static int isinstack (CallInfo *ci, const TValue *o) { - StkId pos; - for (pos = ci->func.p + 1; pos < ci->top.p; pos++) { - if (o == s2v(pos)) - return 1; +static int instack (CallInfo *ci, const TValue *o) { + int pos; + StkId base = ci->func.p + 1; + for (pos = 0; base + pos < ci->top.p; pos++) { + if (o == s2v(base + pos)) + return pos; } - return 0; /* not found */ + return -1; /* not found */ } @@ -708,9 +709,11 @@ static const char *varinfo (lua_State *L, const TValue *o) { const char *kind = NULL; if (isLua(ci)) { kind = getupvalname(ci, o, &name); /* check whether 'o' is an upvalue */ - if (!kind && isinstack(ci, o)) /* no? try a register */ - kind = getobjname(ci_func(ci)->p, currentpc(ci), - cast_int(cast(StkId, o) - (ci->func.p + 1)), &name); + if (!kind) { /* not an upvalue? */ + int reg = instack(ci, o); /* try a register */ + if (reg >= 0) /* is 'o' a register? */ + kind = getobjname(ci_func(ci)->p, currentpc(ci), reg, &name); + } } return formatvarinfo(L, kind, name); }