[PULL,02/23] Revert "host/i386: assume presence of POPCNT"

Commit Message

Paolo Bonzini June 28, 2024, 5:28 p.m. UTC

This reverts commit 45ccdbcb24baf99667997fac5cf60318e5e7db51.
The x86-64 instruction set can now be tuned down to x86-64 v1
or i386 Pentium Pro.

Signed-off-by: Paolo Bonzini <[e-mail]>
---
 host/include/i386/host/cpuinfo.h | 1 +
 tcg/i386/tcg-target.h            | 5 +++--
 util/cpuinfo-i386.c              | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

Patch

diff --git a/host/include/i386/host/cpuinfo.h b/host/include/i386/host/cpuinfo.h
index c1e94d75ce1..72f6fad61e5 100644
--- a/host/include/i386/host/cpuinfo.h
+++ b/host/include/i386/host/cpuinfo.h
@@ -11,6 +11,7 @@ 
 #define CPUINFO_ALWAYS          (1u << 0)  /* so cpuinfo is nonzero */
 #define CPUINFO_MOVBE           (1u << 2)
 #define CPUINFO_LZCNT           (1u << 3)
+#define CPUINFO_POPCNT          (1u << 4)
 #define CPUINFO_BMI1            (1u << 5)
 #define CPUINFO_BMI2            (1u << 6)
 #define CPUINFO_AVX1            (1u << 9)
diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h
index ecc69827287..2f67a97e059 100644
--- a/tcg/i386/tcg-target.h
+++ b/tcg/i386/tcg-target.h
@@ -111,6 +111,7 @@  typedef enum {
 #endif
 
 #define have_bmi1         (cpuinfo & CPUINFO_BMI1)
+#define have_popcnt       (cpuinfo & CPUINFO_POPCNT)
 #define have_avx1         (cpuinfo & CPUINFO_AVX1)
 #define have_avx2         (cpuinfo & CPUINFO_AVX2)
 #define have_movbe        (cpuinfo & CPUINFO_MOVBE)
@@ -142,7 +143,7 @@  typedef enum {
 #define TCG_TARGET_HAS_nor_i32          0
 #define TCG_TARGET_HAS_clz_i32          1
 #define TCG_TARGET_HAS_ctz_i32          1
-#define TCG_TARGET_HAS_ctpop_i32        1
+#define TCG_TARGET_HAS_ctpop_i32        have_popcnt
 #define TCG_TARGET_HAS_deposit_i32      1
 #define TCG_TARGET_HAS_extract_i32      1
 #define TCG_TARGET_HAS_sextract_i32     1
@@ -177,7 +178,7 @@  typedef enum {
 #define TCG_TARGET_HAS_nor_i64          0
 #define TCG_TARGET_HAS_clz_i64          1
 #define TCG_TARGET_HAS_ctz_i64          1
-#define TCG_TARGET_HAS_ctpop_i64        1
+#define TCG_TARGET_HAS_ctpop_i64        have_popcnt
 #define TCG_TARGET_HAS_deposit_i64      1
 #define TCG_TARGET_HAS_extract_i64      1
 #define TCG_TARGET_HAS_sextract_i64     0
diff --git a/util/cpuinfo-i386.c b/util/cpuinfo-i386.c
index 8f2694d88f2..6d474a6259a 100644
--- a/util/cpuinfo-i386.c
+++ b/util/cpuinfo-i386.c
@@ -35,6 +35,7 @@  unsigned __attribute__((constructor)) cpuinfo_init(void)
         __cpuid(1, a, b, c, d);
 
         info |= (c & bit_MOVBE ? CPUINFO_MOVBE : 0);
+        info |= (c & bit_POPCNT ? CPUINFO_POPCNT : 0);
         info |= (c & bit_PCLMUL ? CPUINFO_PCLMUL : 0);
 
         /* NOTE: our AES support requires SSSE3 (PSHUFB) as well. */