# HG changeset patch
# User sviswanathan
# Date 1574785179 -10800
# Node ID dff8053bdb742cb5ac33535fe9aac642ff217e6f
# Parent  f9905e7c96aa5a7d44c53ddb957ab7fc1541f1e1
8234610: MaxVectorSize set wrongly when UseAVX=3 is specified after JDK-8221092
Reviewed-by: kvn, vlivanov

diff -r f9905e7c96aa -r dff8053bdb74 src/hotspot/cpu/x86/vm_version_x86.cpp
--- a/src/hotspot/cpu/x86/vm_version_x86.cpp	Tue Nov 26 19:18:07 2019 +0300
+++ b/src/hotspot/cpu/x86/vm_version_x86.cpp	Tue Nov 26 19:19:39 2019 +0300
@@ -367,26 +367,29 @@
     //
     intx saved_useavx = UseAVX;
     intx saved_usesse = UseSSE;
-    // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
-    __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
-    __ movl(rax, 0x10000);
-    __ andl(rax, Address(rsi, 4)); // xcr0 bits sse | ymm
-    __ cmpl(rax, 0x10000);
-    __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
-    // check _cpuid_info.xem_xcr0_eax.bits.opmask
-    // check _cpuid_info.xem_xcr0_eax.bits.zmm512
-    // check _cpuid_info.xem_xcr0_eax.bits.zmm32
-    __ movl(rax, 0xE0);
-    __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
-    __ cmpl(rax, 0xE0);
-    __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
 
-    __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
-    __ movl(rax, Address(rsi, 0));
-    __ cmpl(rax, 0x50654);              // If it is Skylake
-    __ jcc(Assembler::equal, legacy_setup);
     // If UseAVX is unitialized or is set by the user to include EVEX
     if (use_evex) {
+      // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
+      __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
+      __ movl(rax, 0x10000);
+      __ andl(rax, Address(rsi, 4)); // xcr0 bits sse | ymm
+      __ cmpl(rax, 0x10000);
+      __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
+      // check _cpuid_info.xem_xcr0_eax.bits.opmask
+      // check _cpuid_info.xem_xcr0_eax.bits.zmm512
+      // check _cpuid_info.xem_xcr0_eax.bits.zmm32
+      __ movl(rax, 0xE0);
+      __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
+      __ cmpl(rax, 0xE0);
+      __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
+
+      if (FLAG_IS_DEFAULT(UseAVX)) {
+        __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
+        __ movl(rax, Address(rsi, 0));
+        __ cmpl(rax, 0x50654);              // If it is Skylake
+        __ jcc(Assembler::equal, legacy_setup);
+      }
       // EVEX setup: run in lowest evex mode
       VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts
       UseAVX = 3;
@@ -455,27 +458,28 @@
     VM_Version::set_cpuinfo_cont_addr(__ pc());
     // Returns here after signal. Save xmm0 to check it later.
 
-    // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
-    __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
-    __ movl(rax, 0x10000);
-    __ andl(rax, Address(rsi, 4));
-    __ cmpl(rax, 0x10000);
-    __ jcc(Assembler::notEqual, legacy_save_restore);
-    // check _cpuid_info.xem_xcr0_eax.bits.opmask
-    // check _cpuid_info.xem_xcr0_eax.bits.zmm512
-    // check _cpuid_info.xem_xcr0_eax.bits.zmm32
-    __ movl(rax, 0xE0);
-    __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
-    __ cmpl(rax, 0xE0);
-    __ jcc(Assembler::notEqual, legacy_save_restore);
-
-    __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
-    __ movl(rax, Address(rsi, 0));
-    __ cmpl(rax, 0x50654);              // If it is Skylake
-    __ jcc(Assembler::equal, legacy_save_restore);
-
     // If UseAVX is unitialized or is set by the user to include EVEX
     if (use_evex) {
+      // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
+      __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
+      __ movl(rax, 0x10000);
+      __ andl(rax, Address(rsi, 4));
+      __ cmpl(rax, 0x10000);
+      __ jcc(Assembler::notEqual, legacy_save_restore);
+      // check _cpuid_info.xem_xcr0_eax.bits.opmask
+      // check _cpuid_info.xem_xcr0_eax.bits.zmm512
+      // check _cpuid_info.xem_xcr0_eax.bits.zmm32
+      __ movl(rax, 0xE0);
+      __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
+      __ cmpl(rax, 0xE0);
+      __ jcc(Assembler::notEqual, legacy_save_restore);
+
+      if (FLAG_IS_DEFAULT(UseAVX)) {
+        __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
+        __ movl(rax, Address(rsi, 0));
+        __ cmpl(rax, 0x50654);              // If it is Skylake
+        __ jcc(Assembler::equal, legacy_save_restore);
+      }
       // EVEX check: run in lowest evex mode
       VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts
       UseAVX = 3;