Commit 6a5b69a9 authored by Olivier Danet's avatar Olivier Danet Committed by Mark Cave-Ayland
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target-sparc: fix 32bit integer division overflow 



The signed integer division -0x8000_0000_0000_0000 / -1 must be handled
separately to avoid an overflow on the QEMU host.

Negative overflow must be a negative number for correct sign
extension in Sparc64 mode. Use <stdint.h> constants.

Signed-off-by: default avatarOlivier Danet <odanet@caramail.com>
Signed-off-by: default avatarMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
parent db237e33

target-sparc/helper.c

+10 −7
Original line number Diff line number Diff line
@@ -85,8 +85,8 @@ static target_ulong helper_udiv_common(CPUSPARCState *env, target_ulong a, 
    }



    x0 = x0 / x1;

    if (x0 > 0xffffffff) {

        x0 = 0xffffffff;

    if (x0 > UINT32_MAX) {

        x0 = UINT32_MAX;

        overflow = 1;

    }
@@ -122,13 +122,16 @@ static target_ulong helper_sdiv_common(CPUSPARCState *env, target_ulong a, 
    if (x1 == 0) {

        cpu_restore_state(CPU(cpu), GETPC());

        helper_raise_exception(env, TT_DIV_ZERO);

    }



    } else if (x1 == -1 && x0 == INT64_MIN) {

        x0 = INT32_MAX;

        overflow = 1;

    } else {

        x0 = x0 / x1;

        if ((int32_t) x0 != x0) {

        x0 = x0 < 0 ? 0x80000000 : 0x7fffffff;

            x0 = x0 < 0 ? INT32_MIN : INT32_MAX;

            overflow = 1;

        }

    }



    if (cc) {

        env->cc_dst = x0;