From: Richard Henderson Date: Sat, 14 Jan 2023 23:32:06 +0000 (-1000) Subject: target/i386: Fix BZHI instruction X-Git-Tag: qemu-xen-4.18.0-rc5^2~1^2~150 X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=f163cf6be4b7b51f7327d264ea2572f8b495d287;p=qemu-xen.git target/i386: Fix BZHI instruction We did not correctly handle N >= operand size. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1374 Signed-off-by: Richard Henderson Message-Id: <20230114233206.3118472-1-richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini (cherry picked from commit 9ad2ba6e8e7fc195d0dd0b76ab38bd2fceb1bdd4) Signed-off-by: Michael Tokarev --- diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc index 0d7c6e80ae..7296f3952c 100644 --- a/target/i386/tcg/emit.c.inc +++ b/target/i386/tcg/emit.c.inc @@ -1145,20 +1145,20 @@ static void gen_BLSR(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode) static void gen_BZHI(DisasContext *s, CPUX86State *env, X86DecodedInsn *decode) { MemOp ot = decode->op[0].ot; - TCGv bound; + TCGv bound = tcg_constant_tl(ot == MO_64 ? 63 : 31); + TCGv zero = tcg_constant_tl(0); + TCGv mone = tcg_constant_tl(-1); - tcg_gen_ext8u_tl(s->T1, cpu_regs[s->vex_v]); - bound = tcg_constant_tl(ot == MO_64 ? 63 : 31); + tcg_gen_ext8u_tl(s->T1, s->T1); /* * Note that since we're using BMILG (in order to get O * cleared) we need to store the inverse into C. */ - tcg_gen_setcond_tl(TCG_COND_LT, cpu_cc_src, s->T1, bound); - tcg_gen_movcond_tl(TCG_COND_GT, s->T1, s->T1, bound, bound, s->T1); + tcg_gen_setcond_tl(TCG_COND_LEU, cpu_cc_src, s->T1, bound); - tcg_gen_movi_tl(s->A0, -1); - tcg_gen_shl_tl(s->A0, s->A0, s->T1); + tcg_gen_shl_tl(s->A0, mone, s->T1); + tcg_gen_movcond_tl(TCG_COND_LEU, s->A0, s->T1, bound, s->A0, zero); tcg_gen_andc_tl(s->T0, s->T0, s->A0); gen_op_update1_cc(s); diff --git a/tests/tcg/i386/test-i386-bmi2.c b/tests/tcg/i386/test-i386-bmi2.c index 982d4abda4..0244df7987 100644 --- a/tests/tcg/i386/test-i386-bmi2.c +++ b/tests/tcg/i386/test-i386-bmi2.c @@ -123,6 +123,9 @@ int main(int argc, char *argv[]) { result = bzhiq(mask, 0x1f); assert(result == (mask & ~(-1 << 30))); + result = bzhiq(mask, 0x40); + assert(result == mask); + result = rorxq(0x2132435465768798, 8); assert(result == 0x9821324354657687);