From: Jan Beulich <jbeulich@suse.com>
Date: Fri, 14 Feb 2025 08:35:07 +0000 (+0100)
Subject: x86: correct ISA-used version recording
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b5cb46b155500a87e27ffd4ee3c6b2fca6b82d5d;p=thirdparty%2Fbinutils-gdb.git

x86: correct ISA-used version recording

Updating should be based solely on the current instruction. For example,
recording of VEX-encoded insns as v3 should be independent of there
being earlier AMX insns.

Further for BASELINE only a very limited set of the
GNU_PROPERTY_X86_FEATURE_2_* bits should actually be taken into account:
Most of the bits represent advanced (later) features (XSAVE, XSAVEOPT,
and XSAVEC for example being part of v3).
---

diff --git a/gas/config/tc-i386.c b/gas/config/tc-i386.c
index 246942a378d..9adf8d5748b 100644
--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -12234,21 +12234,23 @@ output_insn (const struct last_insn *last_insn)
 #ifdef OBJ_ELF
   if (x86_used_note && now_seg != absolute_section)
     {
+      unsigned int feature_2_used = 0;
+
       if ((i.xstate & xstate_tmm) == xstate_tmm
 	  || is_cpu (&i.tm, CpuAMX_TILE))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_TMM;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_TMM;
 
       if (is_cpu (&i.tm, Cpu8087)
 	  || is_cpu (&i.tm, Cpu287)
 	  || is_cpu (&i.tm, Cpu387)
 	  || is_cpu (&i.tm, Cpu687)
 	  || is_cpu (&i.tm, CpuFISTTP))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_X87;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_X87;
 
       if ((i.xstate & xstate_mmx)
 	  || i.tm.mnem_off == MN_emms
 	  || i.tm.mnem_off == MN_femms)
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_MMX;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_MMX;
 
       if (i.index_reg)
 	{
@@ -12271,25 +12273,29 @@ output_insn (const struct last_insn *last_insn)
 		  || is_cpu (&i.tm, CpuAVX)))
 	  || is_cpu (&i.tm, CpuWideKL)
 	  || is_cpu (&i.tm, CpuKL))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XMM;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XMM;
 
       if ((i.xstate & xstate_ymm) == xstate_ymm)
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_YMM;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_YMM;
       if ((i.xstate & xstate_zmm) == xstate_zmm)
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_ZMM;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_ZMM;
       if (i.mask.reg || (i.xstate & xstate_mask) == xstate_mask)
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_MASK;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_MASK;
       if (is_cpu (&i.tm, CpuFXSR))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_FXSR;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_FXSR;
       if (is_cpu (&i.tm, CpuXsave))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVE;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVE;
       if (is_cpu (&i.tm, CpuXsaveopt))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVEOPT;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVEOPT;
       if (is_cpu (&i.tm, CpuXSAVEC))
-	x86_feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVEC;
+	feature_2_used |= GNU_PROPERTY_X86_FEATURE_2_XSAVEC;
+
+      x86_feature_2_used |= feature_2_used;
 
       if (object_64bit
-	  || x86_feature_2_used
+	  || (feature_2_used
+	      & (GNU_PROPERTY_X86_FEATURE_2_XMM
+		 | GNU_PROPERTY_X86_FEATURE_2_FXSR)) != 0
 	  || is_cpu (&i.tm, CpuCMOV)
 	  || is_cpu (&i.tm, CpuSYSCALL)
 	  || i.tm.mnem_off == MN_cmpxchg8b)
@@ -12317,13 +12323,13 @@ output_insn (const struct last_insn *last_insn)
 	      && !is_cpu (&i.tm, CpuFMA4)
 	      && !is_cpu (&i.tm, CpuLWP)
 	      && !is_cpu (&i.tm, CpuTBM)
-	      && !(x86_feature_2_used & GNU_PROPERTY_X86_FEATURE_2_TMM))
+	      && !(feature_2_used & GNU_PROPERTY_X86_FEATURE_2_TMM))
 	  || is_cpu (&i.tm, CpuF16C)
 	  || is_cpu (&i.tm, CpuFMA)
 	  || is_cpu (&i.tm, CpuLZCNT)
 	  || is_cpu (&i.tm, CpuMovbe)
 	  || is_cpu (&i.tm, CpuXSAVES)
-	  || (x86_feature_2_used
+	  || (feature_2_used
 	      & (GNU_PROPERTY_X86_FEATURE_2_XSAVE
 		 | GNU_PROPERTY_X86_FEATURE_2_XSAVEOPT
 		 | GNU_PROPERTY_X86_FEATURE_2_XSAVEC)) != 0)
diff --git a/gas/testsuite/gas/i386/property-6.d b/gas/testsuite/gas/i386/property-6.d
index a7dab96232f..2120bc714a6 100644
--- a/gas/testsuite/gas/i386/property-6.d
+++ b/gas/testsuite/gas/i386/property-6.d
@@ -5,5 +5,5 @@
 Displaying notes found in: .note.gnu.property
 [ 	]+Owner[ 	]+Data size[ 	]+Description
   GNU                  0x[0-9a-f]+	NT_GNU_PROPERTY_TYPE_0
-      Properties: x86 ISA used: x86-64-baseline, x86-64-v4
+      Properties: x86 ISA used: (x86-64-baseline, )?x86-64-v4
 	x86 feature used: x86, MASK