Enable AVX and AVX512 features only if their states are supported by
OSXSAVE.
OK for trunk and release branches?
H.J.
---
PR target/85100
* config/i386/cpuinfo.c (XCR_XFEATURE_ENABLED_MASK): New.
(XSTATE_FP): Likewise.
(XSTATE_SSE): Likewise.
(XSTATE_YMM): Likewise.
(XSTATE_OPMASK): Likewise.
(XSTATE_ZMM): Likewise.
(XSTATE_HI_ZMM): Likewise.
(XCR_AVX_ENABLED_MASK): Likewise.
(XCR_AVX512F_ENABLED_MASK): Likewise.
(get_available_features): Enable AVX and AVX512 features only
if their states are supported by OSXSAVE.
---
libgcc/config/i386/cpuinfo.c | 134 +++++++++++++++++++++++++++++--------------
1 file changed, 90 insertions(+), 44 deletions(-)
diff --git a/libgcc/config/i386/cpuinfo.c b/libgcc/config/i386/cpuinfo.c
index 4eb3f5cd944..1dac110a79a 100644
--- a/libgcc/config/i386/cpuinfo.c
+++ b/libgcc/config/i386/cpuinfo.c
@@ -240,6 +240,40 @@ get_available_features (unsigned int ecx, unsigned int edx,
unsigned int features = 0;
unsigned int features2 = 0;
+ /* Get XCR_XFEATURE_ENABLED_MASK register with xgetbv. */
+#define XCR_XFEATURE_ENABLED_MASK 0x0
+#define XSTATE_FP 0x1
+#define XSTATE_SSE 0x2
+#define XSTATE_YMM 0x4
+#define XSTATE_OPMASK 0x20
+#define XSTATE_ZMM 0x40
+#define XSTATE_HI_ZMM 0x80
+
+#define XCR_AVX_ENABLED_MASK \
+ (XSTATE_SSE | XSTATE_YMM)
+#define XCR_AVX512F_ENABLED_MASK \
+ (XSTATE_SSE | XSTATE_YMM | XSTATE_OPMASK | XSTATE_ZMM | XSTATE_HI_ZMM)
+
+ /* Check if AVX and AVX512 are usable. */
+ int avx_usable = 0;
+ int avx512_usable = 0;
+ if ((ecx & bit_OSXSAVE))
+ {
+ /* Check if XMM, YMM, OPMASK, upper 256 bits of ZMM0-ZMM15 and
+ ZMM16-ZMM31 states are supported by OSXSAVE. */
+ unsigned int xcrlow;
+ unsigned int xcrhigh;
+ asm (".byte 0x0f, 0x01, 0xd0"
+ : "=a" (xcrlow), "=d" (xcrhigh)
+ : "c" (XCR_XFEATURE_ENABLED_MASK));
+ if ((xcrlow & XCR_AVX_ENABLED_MASK) == XCR_AVX_ENABLED_MASK)
+ {
+ avx_usable = 1;
+ avx512_usable = ((xcrlow & XCR_AVX512F_ENABLED_MASK)
+ == XCR_AVX512F_ENABLED_MASK);
+ }
+ }
+
#define set_feature(f) \
if (f < 32) features |= (1U << f); else features2 |= (1U << (f - 32))
@@ -265,10 +299,13 @@ get_available_features (unsigned int ecx, unsigned int
edx,
set_feature (FEATURE_SSE4_1);
if (ecx & bit_SSE4_2)
set_feature (FEATURE_SSE4_2);
- if (ecx & bit_AVX)
- set_feature (FEATURE_AVX);
- if (ecx & bit_FMA)
- set_feature (FEATURE_FMA);
+ if (avx_usable)
+ {
+ if (ecx & bit_AVX)
+ set_feature (FEATURE_AVX);
+ if (ecx & bit_FMA)
+ set_feature (FEATURE_FMA);
+ }
/* Get Advanced Features at level 7 (eax = 7, ecx = 0). */
if (max_cpuid_level >= 7)
@@ -276,44 +313,50 @@ get_available_features (unsigned int ecx, unsigned int
edx,
__cpuid_count (7, 0, eax, ebx, ecx, edx);
if (ebx & bit_BMI)
set_feature (FEATURE_BMI);
- if (ebx & bit_AVX2)
- set_feature (FEATURE_AVX2);
+ if (avx_usable)
+ {
+ if (ebx & bit_AVX2)
+ set_feature (FEATURE_AVX2);
+ }
if (ebx & bit_BMI2)
set_feature (FEATURE_BMI2);
- if (ebx & bit_AVX512F)
- set_feature (FEATURE_AVX512F);
- if (ebx & bit_AVX512VL)
- set_feature (FEATURE_AVX512VL);
- if (ebx & bit_AVX512BW)
- set_feature (FEATURE_AVX512BW);
- if (ebx & bit_AVX512DQ)
- set_feature (FEATURE_AVX512DQ);
- if (ebx & bit_AVX512CD)
- set_feature (FEATURE_AVX512CD);
- if (ebx & bit_AVX512PF)
- set_feature (FEATURE_AVX512PF);
- if (ebx & bit_AVX512ER)
- set_feature (FEATURE_AVX512ER);
- if (ebx & bit_AVX512IFMA)
- set_feature (FEATURE_AVX512IFMA);
- if (ecx & bit_AVX512VBMI)
- set_feature (FEATURE_AVX512VBMI);
- if (ecx & bit_AVX512VBMI2)
- set_feature (FEATURE_AVX512VBMI2);
- if (ecx & bit_GFNI)
- set_feature (FEATURE_GFNI);
- if (ecx & bit_VPCLMULQDQ)
- set_feature (FEATURE_VPCLMULQDQ);
- if (ecx & bit_AVX512VNNI)
- set_feature (FEATURE_AVX512VNNI);
- if (ecx & bit_AVX512BITALG)
- set_feature (FEATURE_AVX512BITALG);
- if (ecx & bit_AVX512VPOPCNTDQ)
- set_feature (FEATURE_AVX512VPOPCNTDQ);
- if (edx & bit_AVX5124VNNIW)
- set_feature (FEATURE_AVX5124VNNIW);
- if (edx & bit_AVX5124FMAPS)
- set_feature (FEATURE_AVX5124FMAPS);
+ if (avx512_usable)
+ {
+ if (ebx & bit_AVX512F)
+ set_feature (FEATURE_AVX512F);
+ if (ebx & bit_AVX512VL)
+ set_feature (FEATURE_AVX512VL);
+ if (ebx & bit_AVX512BW)
+ set_feature (FEATURE_AVX512BW);
+ if (ebx & bit_AVX512DQ)
+ set_feature (FEATURE_AVX512DQ);
+ if (ebx & bit_AVX512CD)
+ set_feature (FEATURE_AVX512CD);
+ if (ebx & bit_AVX512PF)
+ set_feature (FEATURE_AVX512PF);
+ if (ebx & bit_AVX512ER)
+ set_feature (FEATURE_AVX512ER);
+ if (ebx & bit_AVX512IFMA)
+ set_feature (FEATURE_AVX512IFMA);
+ if (ecx & bit_AVX512VBMI)
+ set_feature (FEATURE_AVX512VBMI);
+ if (ecx & bit_AVX512VBMI2)
+ set_feature (FEATURE_AVX512VBMI2);
+ if (ecx & bit_GFNI)
+ set_feature (FEATURE_GFNI);
+ if (ecx & bit_VPCLMULQDQ)
+ set_feature (FEATURE_VPCLMULQDQ);
+ if (ecx & bit_AVX512VNNI)
+ set_feature (FEATURE_AVX512VNNI);
+ if (ecx & bit_AVX512BITALG)
+ set_feature (FEATURE_AVX512BITALG);
+ if (ecx & bit_AVX512VPOPCNTDQ)
+ set_feature (FEATURE_AVX512VPOPCNTDQ);
+ if (edx & bit_AVX5124VNNIW)
+ set_feature (FEATURE_AVX5124VNNIW);
+ if (edx & bit_AVX5124FMAPS)
+ set_feature (FEATURE_AVX5124FMAPS);
+ }
}
/* Check cpuid level of extended features. */
@@ -325,10 +368,13 @@ get_available_features (unsigned int ecx, unsigned int
edx,
if (ecx & bit_SSE4a)
set_feature (FEATURE_SSE4_A);
- if (ecx & bit_FMA4)
- set_feature (FEATURE_FMA4);
- if (ecx & bit_XOP)
- set_feature (FEATURE_XOP);
+ if (avx_usable)
+ {
+ if (ecx & bit_FMA4)
+ set_feature (FEATURE_FMA4);
+ if (ecx & bit_XOP)
+ set_feature (FEATURE_XOP);
+ }
}
__cpu_model.__cpu_features[0] = features;
--
2.14.3
