diff mbox series

[05/20] tcg/i386: Detect AVX512

Message ID 20211218194250.247633-6-richard.henderson@linaro.org
State Superseded
Headers show
Series tcg: vector improvements | expand

Commit Message

Richard Henderson Dec. 18, 2021, 7:42 p.m. UTC 
There are some operation sizes in some subsets of AVX512 that
are missing from previous iterations of AVX.  Detect them.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/qemu/cpuid.h      | 20 +++++++++++++++++---
 tcg/i386/tcg-target.h     |  4 ++++
 tcg/i386/tcg-target.c.inc | 24 ++++++++++++++++++++++--
 3 files changed, 43 insertions(+), 5 deletions(-)

Comments

Alex Bennée Feb. 1, 2022, 6:41 p.m. UTC | #1 
Richard Henderson <richard.henderson@linaro.org> writes:

> There are some operation sizes in some subsets of AVX512 that
> are missing from previous iterations of AVX.  Detect them.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Hard for me to test but the code looks sane

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
diff mbox series

Patch

diff --git a/include/qemu/cpuid.h b/include/qemu/cpuid.h
index 09fc245b91..7adb12d320 100644
--- a/include/qemu/cpuid.h
+++ b/include/qemu/cpuid.h
@@ -45,12 +45,26 @@ 
 #ifndef bit_AVX2
 #define bit_AVX2        (1 << 5)
 #endif
-#ifndef bit_AVX512F
-#define bit_AVX512F        (1 << 16)
-#endif
 #ifndef bit_BMI2
 #define bit_BMI2        (1 << 8)
 #endif
+#ifndef bit_AVX512F
+#define bit_AVX512F     (1 << 16)
+#endif
+#ifndef bit_AVX512DQ
+#define bit_AVX512DQ    (1 << 17)
+#endif
+#ifndef bit_AVX512BW
+#define bit_AVX512BW    (1 << 30)
+#endif
+#ifndef bit_AVX512VL
+#define bit_AVX512VL    (1u << 31)
+#endif
+
+/* Leaf 7, %ecx */
+#ifndef bit_AVX512VBMI2
+#define bit_AVX512VBMI2 (1 << 6)
+#endif
 
 /* Leaf 0x80000001, %ecx */
 #ifndef bit_LZCNT
diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h
index 64c1013182..12d098ad6c 100644
--- a/tcg/i386/tcg-target.h
+++ b/tcg/i386/tcg-target.h
@@ -103,6 +103,10 @@  extern bool have_bmi1;
 extern bool have_popcnt;
 extern bool have_avx1;
 extern bool have_avx2;
+extern bool have_avx512bw;
+extern bool have_avx512dq;
+extern bool have_avx512vbmi2;
+extern bool have_avx512vl;
 extern bool have_movbe;
 
 /* optional instructions */
diff --git a/tcg/i386/tcg-target.c.inc b/tcg/i386/tcg-target.c.inc
index 84b109bb84..e266f937d6 100644
--- a/tcg/i386/tcg-target.c.inc
+++ b/tcg/i386/tcg-target.c.inc
@@ -170,6 +170,10 @@  bool have_bmi1;
 bool have_popcnt;
 bool have_avx1;
 bool have_avx2;
+bool have_avx512bw;
+bool have_avx512dq;
+bool have_avx512vbmi2;
+bool have_avx512vl;
 bool have_movbe;
 
 #ifdef CONFIG_CPUID_H
@@ -3746,12 +3750,12 @@  static void tcg_out_nop_fill(tcg_insn_unit *p, int count)
 static void tcg_target_init(TCGContext *s)
 {
 #ifdef CONFIG_CPUID_H
-    unsigned a, b, c, d, b7 = 0;
+    unsigned a, b, c, d, b7 = 0, c7 = 0;
     int max = __get_cpuid_max(0, 0);
 
     if (max >= 7) {
         /* BMI1 is available on AMD Piledriver and Intel Haswell CPUs.  */
-        __cpuid_count(7, 0, a, b7, c, d);
+        __cpuid_count(7, 0, a, b7, c7, d);
         have_bmi1 = (b7 & bit_BMI) != 0;
         have_bmi2 = (b7 & bit_BMI2) != 0;
     }
@@ -3781,6 +3785,22 @@  static void tcg_target_init(TCGContext *s)
             if ((xcrl & 6) == 6) {
                 have_avx1 = (c & bit_AVX) != 0;
                 have_avx2 = (b7 & bit_AVX2) != 0;
+
+                /*
+                 * There are interesting instructions in AVX512, so long
+                 * as we have AVX512VL, which indicates support for EVEX
+                 * on sizes smaller than 512 bits.  We are required to
+                 * check that OPMASK and all extended ZMM state are enabled
+                 * even if we're not using them -- the insns will fault.
+                 */
+                if ((xcrl & 0xe0) == 0xe0
+                    && (b7 & bit_AVX512F)
+                    && (b7 & bit_AVX512VL)) {
+                    have_avx512vl = true;
+                    have_avx512bw = (b7 & bit_AVX512BW) != 0;
+                    have_avx512dq = (b7 & bit_AVX512DQ) != 0;
+                    have_avx512vbmi2 = (c7 & bit_AVX512VBMI2) != 0;
+                }
             }
         }
     }