Out-of-range shifts have undefined results, but must not trap.
Mask off immediate shift counts to solve this problem.
This bug can be reproduced by running the following guest instructions:
xor %ecx,%ecx
sar %cl,%eax
cmovne %edi,%eax
After optimization, the tcg opcodes of the sar are
movi_i32 tmp3,$0xffffffffffffffff pref=all
sar_i32 tmp3,eax,tmp3 dead: 2 pref=all
mov_i32 cc_dst,eax sync: 0 dead: 1 pref=0xffc0300
mov_i32 cc_src,tmp3 sync: 0 dead: 0 1 pref=all
movi_i32 cc_op,$0x31 sync: 0 dead: 0 pref=all
The sar_i32 opcode is a shift by -1, which unmasked generates
0x200808d618: fffa5b9b illegal
Signed-off-by: Zihao Yu <yuzihao@ict.ac.cn>
Message-Id: <20201216081206.9628-1-yuzihao@ict.ac.cn>
[rth: Reworded the patch description.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This wasn't actually used for anything, really. All variable
operands must accept registers, and which are indicated by the
set in TCGArgConstraint.regs.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The union is unused; let "regs" appear in the main structure
without the "u.regs" wrapping.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
With Makefiles that have automatically generated dependencies, you
generated includes are set as dependencies of the Makefile, so that they
are built before everything else and they are available when first
building the .c files.
Alternatively you can use a fine-grained dependency, e.g.
target/arm/translate.o: target/arm/decode-neon-shared.inc.c
With Meson you have only one choice and it is a third option, namely
"build at the beginning of the corresponding target"; the way you
express it is to list the includes in the sources of that target.
The problem is that Meson decides if something is a source vs. a
generated include by looking at the extension: '.c', '.cc', '.m', '.C'
are sources, while everything else is considered an include---including
'.inc.c'.
Use '.c.inc' to avoid this, as it is consistent with our other convention
of using '.rst.inc' for included reStructuredText files. The editorconfig
file is adjusted.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
