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| author | Richard Henderson | 2018-06-15 07:57:03 +0200 |
|---|---|---|
| committer | Richard Henderson | 2018-06-15 21:39:53 +0200 |
| commit | 9f754620651d3432114f4bb89c7f12cbea814b3e (patch) | |
| tree | 7450e7708caa0ef187fc4fb66d62695e33a2c82b /tcg/sparc | |
| parent | tcg: remove tb_lock (diff) | |
| download | qemu-9f754620651d3432114f4bb89c7f12cbea814b3e.tar.gz qemu-9f754620651d3432114f4bb89c7f12cbea814b3e.tar.xz qemu-9f754620651d3432114f4bb89c7f12cbea814b3e.zip | |
tcg: Reduce max TB opcode count
Also, assert that we don't overflow any of two different offsets into
the TB. Both unwind and goto_tb both record a uint16_t for later use.
This fixes an arm-softmmu test case utilizing NEON in which there is
a TB generated that runs to 7800 opcodes, and compiles to 96k on an
x86_64 host. This overflows the 16-bit offset in which we record the
goto_tb reset offset. Because of that overflow, we install a jump
destination that goes to neverland. Boom.
With this reduced op count, the same TB compiles to about 48k for
aarch64, ppc64le, and x86_64 hosts, and neither assertion fires.
Cc: qemu-stable@nongnu.org
Reported-by: "Jason A. Donenfeld" <Jason@zx2c4.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'tcg/sparc')
| -rw-r--r-- | tcg/sparc/tcg-target.inc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tcg/sparc/tcg-target.inc.c b/tcg/sparc/tcg-target.inc.c index bc673bd8c6..04bdc3df5e 100644 --- a/tcg/sparc/tcg-target.inc.c +++ b/tcg/sparc/tcg-target.inc.c @@ -1388,12 +1388,12 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, tcg_out_arithi(s, TCG_REG_G0, TCG_REG_TB, 0, JMPL); tcg_out_nop(s); } - s->tb_jmp_reset_offset[a0] = c = tcg_current_code_size(s); + set_jmp_reset_offset(s, a0); /* For the unlinked path of goto_tb, we need to reset TCG_REG_TB to the beginning of this TB. */ if (USE_REG_TB) { - c = -c; + c = -tcg_current_code_size(s); if (check_fit_i32(c, 13)) { tcg_out_arithi(s, TCG_REG_TB, TCG_REG_TB, c, ARITH_ADD); } else { |