[xen master] x86emul: correct EFLAGS testing for BMI1/BMI2

[patchbot@xxxxxxx]

commit 5b8780869ea7c1023a389d27c536c0c77e8464a5
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Thu Nov 14 13:00:29 2024 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Thu Nov 14 13:00:29 2024 +0100

    x86emul: correct EFLAGS testing for BMI1/BMI2
    
    Apparently I blindly copied the constants from the BEXTR case, where SF
    indeed wants leaving out. For BLSI, BLSMSK, BLSR, and BZHI SF is
    defined, and hence wants checking. This is noticable in particular for
    BLSR, where with the input we use SF will be set in the result (and
    hence is being switched to be clear on input).
    
    Convert to using named constants we have available, while omitting DF,
    TF, as well as the MBZ bits 3 and 5 from the masking values in the
    checks of the produced output. For BZHI also set SF on input, expecting
    it to transition to clear.
    
    Fixes: 771daacd197a ("x86emul: support BMI1 insns")
    Fixes: 8e20924de13d ("x86emul: support BMI2 insns")
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
 tools/tests/x86_emulator/test_x86_emulator.c | 28 ++++++++++++++++++++--------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/tools/tests/x86_emulator/test_x86_emulator.c 
b/tools/tests/x86_emulator/test_x86_emulator.c
index d52c1c53cb..66bb184ccd 100644
--- a/tools/tests/x86_emulator/test_x86_emulator.c
+++ b/tools/tests/x86_emulator/test_x86_emulator.c
@@ -1969,10 +1969,13 @@ int main(int argc, char **argv)
 
         *res        = 0xfedcba98;
         regs.edx    = (unsigned long)res;
-        regs.eflags = 0xac2;
+        regs.eflags = EFLAGS_ALWAYS_SET | X86_EFLAGS_OF | X86_EFLAGS_SF | \
+                      X86_EFLAGS_ZF;
         rc = x86_emulate(&ctxt, &emulops);
         if ( (rc != X86EMUL_OKAY) || regs.ecx != 8 || *res != 0xfedcba98 ||
-             (regs.eflags & 0xf6b) != 0x203 || !check_eip(blsi) )
+             (regs.eflags & (EFLAGS_MASK & ~(X86_EFLAGS_AF | X86_EFLAGS_PF))) 
!=
+              (EFLAGS_ALWAYS_SET | X86_EFLAGS_CF) ||
+             !check_eip(blsi) )
             goto fail;
         printf("okay\n");
     }
@@ -1988,10 +1991,13 @@ int main(int argc, char **argv)
                        :: "d" (NULL) );
         set_insn(blsmsk);
 
-        regs.eflags = 0xac3;
+        regs.eflags = EFLAGS_ALWAYS_SET | X86_EFLAGS_OF | X86_EFLAGS_SF | \
+                      X86_EFLAGS_ZF | X86_EFLAGS_CF;
         rc = x86_emulate(&ctxt, &emulops);
         if ( (rc != X86EMUL_OKAY) || regs.ecx != 0xf || *res != 0xfedcba98 ||
-             (regs.eflags & 0xf6b) != 0x202 || !check_eip(blsmsk) )
+             (regs.eflags & (EFLAGS_MASK & ~(X86_EFLAGS_AF | X86_EFLAGS_PF))) 
!=
+              EFLAGS_ALWAYS_SET ||
+             !check_eip(blsmsk) )
             goto fail;
         printf("okay\n");
     }
@@ -2007,10 +2013,13 @@ int main(int argc, char **argv)
                        :: "d" (NULL) );
         set_insn(blsr);
 
-        regs.eflags = 0xac3;
+        regs.eflags = EFLAGS_ALWAYS_SET | X86_EFLAGS_OF | X86_EFLAGS_ZF | \
+                      X86_EFLAGS_CF;
         rc = x86_emulate(&ctxt, &emulops);
         if ( (rc != X86EMUL_OKAY) || regs.ecx != 0xfedcba90 ||
-             (regs.eflags & 0xf6b) != 0x202 || !check_eip(blsr) )
+             (regs.eflags & (EFLAGS_MASK & ~(X86_EFLAGS_AF | X86_EFLAGS_PF))) 
!=
+              (EFLAGS_ALWAYS_SET | X86_EFLAGS_SF) ||
+             !check_eip(blsr) )
             goto fail;
         printf("okay\n");
     }
@@ -2028,11 +2037,14 @@ int main(int argc, char **argv)
 
         regs.ecx    = (unsigned long)res;
         regs.edx    = 0xff13;
-        regs.eflags = 0xa43;
+        regs.eflags = EFLAGS_ALWAYS_SET | X86_EFLAGS_OF | X86_EFLAGS_SF | \
+                      X86_EFLAGS_ZF | X86_EFLAGS_CF;
         rc = x86_emulate(&ctxt, &emulops);
         if ( (rc != X86EMUL_OKAY) || regs.ebx != (*res & 0x7ffff) ||
              regs.edx != 0xff13 || *res != 0xfedcba98 ||
-             (regs.eflags & 0xf6b) != 0x202 || !check_eip(bzhi) )
+             (regs.eflags & (EFLAGS_MASK & ~(X86_EFLAGS_AF | X86_EFLAGS_PF))) 
!=
+              EFLAGS_ALWAYS_SET ||
+             !check_eip(bzhi) )
             goto fail;
         printf("okay\n");
     }
--
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