Commit 94248cfc authored by Catherine A. Frederick's avatar Catherine A. Frederick Committed by Richard Henderson
Browse files

tcg/ppc: Sanitize immediate shifts 



Sanitize shift constants so that shift operations with
large constants don't generate invalid instructions.

Signed-off-by: default avatarCatherine A. Frederick <chocola@animebitch.es>
Message-Id: <20200607211100.22858-1-agrecascino123@gmail.com>
Signed-off-by: default avatarRichard Henderson <richard.henderson@linaro.org>
parent eb6490f5

tcg/ppc/tcg-target.inc.c

+10 −5
Original line number Diff line number Diff line
@@ -2610,21 +2610,24 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args, 


    case INDEX_op_shl_i32:

        if (const_args[2]) {

            tcg_out_shli32(s, args[0], args[1], args[2]);

            /* Limit immediate shift count lest we create an illegal insn.  */

            tcg_out_shli32(s, args[0], args[1], args[2] & 31);

        } else {

            tcg_out32(s, SLW | SAB(args[1], args[0], args[2]));

        }

        break;

    case INDEX_op_shr_i32:

        if (const_args[2]) {

            tcg_out_shri32(s, args[0], args[1], args[2]);

            /* Limit immediate shift count lest we create an illegal insn.  */

            tcg_out_shri32(s, args[0], args[1], args[2] & 31);

        } else {

            tcg_out32(s, SRW | SAB(args[1], args[0], args[2]));

        }

        break;

    case INDEX_op_sar_i32:

        if (const_args[2]) {

            tcg_out32(s, SRAWI | RS(args[1]) | RA(args[0]) | SH(args[2]));

            /* Limit immediate shift count lest we create an illegal insn.  */

            tcg_out32(s, SRAWI | RS(args[1]) | RA(args[0]) | SH(args[2] & 31));

        } else {

            tcg_out32(s, SRAW | SAB(args[1], args[0], args[2]));

        }
@@ -2696,14 +2699,16 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args, 


    case INDEX_op_shl_i64:

        if (const_args[2]) {

            tcg_out_shli64(s, args[0], args[1], args[2]);

            /* Limit immediate shift count lest we create an illegal insn.  */

            tcg_out_shli64(s, args[0], args[1], args[2] & 63);

        } else {

            tcg_out32(s, SLD | SAB(args[1], args[0], args[2]));

        }

        break;

    case INDEX_op_shr_i64:

        if (const_args[2]) {

            tcg_out_shri64(s, args[0], args[1], args[2]);

            /* Limit immediate shift count lest we create an illegal insn.  */

            tcg_out_shri64(s, args[0], args[1], args[2] & 63);

        } else {

            tcg_out32(s, SRD | SAB(args[1], args[0], args[2]));

        }