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tcg: Fix out of range shift in deposit optimizations

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By inspection, for a deposit(x, y, 0, 64), we'd have a shift of (1<<64)
and everything else falls apart.  But we can reuse the existing deposit
logic to get this right.

Signed-off-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Richard Henderson 2014-03-18 14:23:52 -07:00
parent 1976cccec8
commit d998e555d2
1 changed files with 4 additions and 6 deletions
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10
tcg/optimize.c
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@ -843,9 +843,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
break;
CASE_OP_32_64(deposit):
tmp = ((1ull << args[4]) - 1);
mask = ((temps[args[1]].mask & ~(tmp << args[3]))
| ((temps[args[2]].mask & tmp) << args[3]));
mask = deposit64(temps[args[1]].mask, args[3], args[4],
temps[args[2]].mask);
break;
CASE_OP_32_64(or):
@ -1060,9 +1059,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr,
if (temps[args[1]].state == TCG_TEMP_CONST
&& temps[args[2]].state == TCG_TEMP_CONST) {
s->gen_opc_buf[op_index] = op_to_movi(op);
tmp = ((1ull << args[4]) - 1);
tmp = (temps[args[1]].val & ~(tmp << args[3]))
| ((temps[args[2]].val & tmp) << args[3]);
tmp = deposit64(temps[args[1]].val, args[3], args[4],
temps[args[2]].val);
tcg_opt_gen_movi(gen_args, args[0], tmp);
gen_args += 2;
args += 5;