Commit 450445d5 authored by Richard Henderson's avatar Richard Henderson
Browse files

tcg: Fix tcg_reg_alloc_mov vs no-op truncation 



Commit af3cbfbe hoisted some "common"
loads of the temporary type, forgetting that the types could differ
during truncating moves.  This affects the correctness of the memory
offset on big-endian hosts.

Tested-by: default avatarTom Musta <tommusta@gmail.com>
Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent f30d56e7

tcg/tcg.c

+11 −8
Original line number Diff line number Diff line
@@ -2096,12 +2096,15 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def, 
{

    TCGRegSet allocated_regs;

    TCGTemp *ts, *ots;

    TCGType type;

    TCGType otype, itype;



    tcg_regset_set(allocated_regs, s->reserved_regs);

    ots = &s->temps[args[0]];

    ts = &s->temps[args[1]];

    type = ots->type;



    /* Note that otype != itype for no-op truncation.  */

    otype = ots->type;

    itype = ts->type;



    /* If the source value is not in a register, and we're going to be

       forced to have it in a register in order to perform the copy,
@@ -2109,13 +2112,13 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def, 
       we don't have to reload SOURCE the next time it is used. */

    if (((NEED_SYNC_ARG(0) || ots->fixed_reg) && ts->val_type != TEMP_VAL_REG)

        || ts->val_type == TEMP_VAL_MEM) {

        ts->reg = tcg_reg_alloc(s, tcg_target_available_regs[type],

        ts->reg = tcg_reg_alloc(s, tcg_target_available_regs[itype],

                                allocated_regs);

        if (ts->val_type == TEMP_VAL_MEM) {

            tcg_out_ld(s, type, ts->reg, ts->mem_reg, ts->mem_offset);

            tcg_out_ld(s, itype, ts->reg, ts->mem_reg, ts->mem_offset);

            ts->mem_coherent = 1;

        } else if (ts->val_type == TEMP_VAL_CONST) {

            tcg_out_movi(s, type, ts->reg, ts->val);

            tcg_out_movi(s, itype, ts->reg, ts->val);

        }

        s->reg_to_temp[ts->reg] = args[1];

        ts->val_type = TEMP_VAL_REG;
@@ -2130,7 +2133,7 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def, 
        if (!ots->mem_allocated) {

            temp_allocate_frame(s, args[0]);

        }

        tcg_out_st(s, type, ts->reg, ots->mem_reg, ots->mem_offset);

        tcg_out_st(s, otype, ts->reg, ots->mem_reg, ots->mem_offset);

        if (IS_DEAD_ARG(1)) {

            temp_dead(s, args[1]);

        }
@@ -2158,10 +2161,10 @@ static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def, 
                /* When allocating a new register, make sure to not spill the

                   input one. */

                tcg_regset_set_reg(allocated_regs, ts->reg);

                ots->reg = tcg_reg_alloc(s, tcg_target_available_regs[type],

                ots->reg = tcg_reg_alloc(s, tcg_target_available_regs[otype],

                                         allocated_regs);

            }

            tcg_out_mov(s, type, ots->reg, ts->reg);

            tcg_out_mov(s, otype, ots->reg, ts->reg);

        }

        ots->val_type = TEMP_VAL_REG;

        ots->mem_coherent = 0;