target/i386: Fix 32-bit AD[CO]X insns in 64-bit mode

Failure to truncate the inputs results in garbage for the carry-out.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1373
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230115012103.3131796-1-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

3 files changed, 74 insertions, 0 deletions

diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc
index 0d7c6e8..e61ae9a 100644
--- a/target/i386/tcg/emit.c.inc
+++ b/target/i386/tcg/emit.c.inc
@@ -1037,6 +1037,8 @@ static void gen_ADCOX(DisasContext *s, CPUX86State *env, MemOp ot, int cc_op)
 #ifdef TARGET_X86_64
     case MO_32:
         /* If TL is 64-bit just do everything in 64-bit arithmetic.  */
+        tcg_gen_ext32u_tl(s->T0, s->T0);
+        tcg_gen_ext32u_tl(s->T1, s->T1);
         tcg_gen_add_i64(s->T0, s->T0, s->T1);
         tcg_gen_add_i64(s->T0, s->T0, carry_in);
         tcg_gen_shri_i64(carry_out, s->T0, 32);
diff --git a/tests/tcg/x86_64/Makefile.target b/tests/tcg/x86_64/Makefile.target
index 4eac782..e64aab1 100644
--- a/tests/tcg/x86_64/Makefile.target
+++ b/tests/tcg/x86_64/Makefile.target
@@ -12,11 +12,14 @@ ifeq ($(filter %-linux-user, $(TARGET)),$(TARGET))
 X86_64_TESTS += vsyscall
 X86_64_TESTS += noexec
 X86_64_TESTS += cmpxchg
+X86_64_TESTS += adox
 TESTS=$(MULTIARCH_TESTS) $(X86_64_TESTS) test-x86_64
 else
 TESTS=$(MULTIARCH_TESTS)
 endif
 
+adox: CFLAGS=-O2
+
 run-test-i386-ssse3: QEMU_OPTS += -cpu max
 run-plugin-test-i386-ssse3-%: QEMU_OPTS += -cpu max
 
diff --git a/tests/tcg/x86_64/adox.c b/tests/tcg/x86_64/adox.c
new file mode 100644
index 0000000..36be644
--- /dev/null
+++ b/tests/tcg/x86_64/adox.c
@@ -0,0 +1,69 @@
+/* See if ADOX give expected results */
+
+#include <assert.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+static uint64_t adoxq(bool *c_out, uint64_t a, uint64_t b, bool c)
+{
+    asm ("addl $0x7fffffff, %k1\n\t"
+         "adoxq %2, %0\n\t"
+         "seto %b1"
+         : "+r"(a), "=&r"(c) : "r"(b), "1"((int)c));
+    *c_out = c;
+    return a;
+}
+
+static uint64_t adoxl(bool *c_out, uint64_t a, uint64_t b, bool c)
+{
+    asm ("addl $0x7fffffff, %k1\n\t"
+         "adoxl %k2, %k0\n\t"
+         "seto %b1"
+         : "+r"(a), "=&r"(c) : "r"(b), "1"((int)c));
+    *c_out = c;
+    return a;
+}
+
+int main()
+{
+    uint64_t r;
+    bool c;
+
+    r = adoxq(&c, 0, 0, 0);
+    assert(r == 0);
+    assert(c == 0);
+
+    r = adoxl(&c, 0, 0, 0);
+    assert(r == 0);
+    assert(c == 0);
+
+    r = adoxl(&c, 0x100000000, 0, 0);
+    assert(r == 0);
+    assert(c == 0);
+
+    r = adoxq(&c, 0, 0, 1);
+    assert(r == 1);
+    assert(c == 0);
+
+    r = adoxl(&c, 0, 0, 1);
+    assert(r == 1);
+    assert(c == 0);
+
+    r = adoxq(&c, -1, -1, 0);
+    assert(r == -2);
+    assert(c == 1);
+
+    r = adoxl(&c, -1, -1, 0);
+    assert(r == 0xfffffffe);
+    assert(c == 1);
+
+    r = adoxq(&c, -1, -1, 1);
+    assert(r == -1);
+    assert(c == 1);
+
+    r = adoxl(&c, -1, -1, 1);
+    assert(r == 0xffffffff);
+    assert(c == 1);
+
+    return 0;
+}