[binutils-gdb] gdb/record: add support for BMI2 instructions

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=1c04308f0958cbac83bad22703758139ea6969b6

commit 1c04308f0958cbac83bad22703758139ea6969b6
Author: Guinevere Larsen <[email protected]>
Date:   Tue Jun 16 16:03:43 2026 -0300

    gdb/record: add support for BMI2 instructions
    
    This commit adds support for recording all instructions in the Bit
    Manipulation Instruction set 2, for x86 cpus. The specific instructions
    are:
    
    * mulx
    * pdep
    * pext
    * rorx
    * sarx
    * sh[r|l]x
    * bzhi
    
    And adds them to the AVX test, for the same reason as the previous
    commit.
    
    Approved-By: Guinevere Larsen <[email protected]>

Diff:
---
 gdb/i386-tdep.c                                | 18 ++++++++++++++++--
 gdb/testsuite/gdb.reverse/i386-avx-reverse.c   | 14 ++++++++++++++
 gdb/testsuite/gdb.reverse/i386-avx-reverse.exp | 14 ++++++++++++++
 3 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c
index bf131aaf96a..f69cc2dcc01 100644
--- a/gdb/i386-tdep.c
+++ b/gdb/i386-tdep.c
@@ -5128,7 +5128,7 @@ i386_record_vex (struct i386_record_s *ir, uint8_t vex_w, uint8_t vex_r,
     case 0xf2:	/* VPSLLD, dynamic shift and ANDN.  */
     case 0xf3:	/* VPSLLQ, dynamic shift and BLSI, BLSR and BLSMSK.  */
     case 0xf4:	/* VPMULUDQ  */
-    case 0xf6:	/* VPSADBW.  */
+    case 0xf6:	/* VPSADBW or MULX.  */
     case 0xfc:	/* VPADDB  */
     case 0xfd:	/* VPADDW  */
     case 0xfe:	/* VPADDD  */
@@ -5152,6 +5152,15 @@ i386_record_vex (struct i386_record_s *ir, uint8_t vex_w, uint8_t vex_r,
 	    record_full_arch_list_add_reg
 	      (ir->regcache, ir->regmap[X86_RECORD_EFLAGS_REGNUM]);
 	  }
+	else if (opcode == 0xf6 && ir->map_select == 2)
+	  {
+	    record_full_arch_list_add_reg (ir->regcache,
+					   ir->regmap[X86_RECORD_REAX_REGNUM
+						      + ir->vvvv]);
+	    record_full_arch_list_add_reg (ir->regcache,
+					   ir->regmap[X86_RECORD_REAX_REGNUM
+						      + reg_offset]);
+	  }
 	else
 	  {
 	    /* This set of instructions all share the same exact way to
@@ -5164,11 +5173,16 @@ i386_record_vex (struct i386_record_s *ir, uint8_t vex_w, uint8_t vex_r,
       }
       break;
 
-    case 0xf7:	/* BEXTR.  */
+    case 0xf0:	/* RORX.  */
+    case 0xf5:	/* PDEP or PEXT or BZHI.  */
+    case 0xf7:	/* BEXTR or SARX or SHLX or SHRX.  */
       i386_record_modrm (ir);
       record_full_arch_list_add_reg (ir->regcache,
 				     ir->regmap[X86_RECORD_REAX_REGNUM
 						+ ir->reg + vex_r * 8]);
+      if (opcode == 0xf5 && ir->pp == 0)
+	record_full_arch_list_add_reg (ir->regcache,
+				       ir->regmap[X86_RECORD_EFLAGS_REGNUM]);
       break;
 
     case 0x2e: /* VUCOMIS[S|D].  */
diff --git a/gdb/testsuite/gdb.reverse/i386-avx-reverse.c b/gdb/testsuite/gdb.reverse/i386-avx-reverse.c
index 190bc6f4a7a..88cd3fc7f34 100644
--- a/gdb/testsuite/gdb.reverse/i386-avx-reverse.c
+++ b/gdb/testsuite/gdb.reverse/i386-avx-reverse.c
@@ -773,6 +773,7 @@ bmi_test ()
      eax = 0x1312
      ebx = 0xdeadbeef
      ecx = 0xcafeface
+     edx = 0x2337
      r8  = 0
      this way it's easy to confirm we're undoing things correctly.  */
 
@@ -799,6 +800,19 @@ bmi_test ()
   asm volatile ("tzcnt %eax, %ebx");
   asm volatile ("tzcnt %ax, %r8w");
 
+  asm volatile ("mulx %eax, %ebx, %ecx");
+  asm volatile ("mulx %ebx, %ecx, %ebx");
+
+  asm volatile ("pdep %r8, %rcx, %rbx");
+  asm volatile ("pext %edx, %ecx, %ebx");
+  asm volatile ("rorx $10, %r8, %rbx");
+  asm volatile ("sarx %edx, %ebx, %eax");
+  asm volatile ("shlx %eax, %ecx, %ebx");
+  asm volatile ("shrx %r8d, %eax, %ecx");
+
+  asm volatile ("bzhi %edx, %ebx, %r8d");
+  asm volatile ("bzhi %rax, %rcx, %r8");
+
   return 0; /* end bmi_test  */
 }
 
diff --git a/gdb/testsuite/gdb.reverse/i386-avx-reverse.exp b/gdb/testsuite/gdb.reverse/i386-avx-reverse.exp
index 811b085f4a6..4fe64a775d8 100644
--- a/gdb/testsuite/gdb.reverse/i386-avx-reverse.exp
+++ b/gdb/testsuite/gdb.reverse/i386-avx-reverse.exp
@@ -1206,9 +1206,23 @@ gdb_test_no_output \
     "set \$eax = 0x1312" "set eax for bmi test"
 gdb_test_no_output "set \$ebx = 0xdeadbeef" "set ebx for bmi test"
 gdb_test_no_output "set \$ecx = 0xcafeface" "set ecx for bmi test"
+gdb_test_no_output "set \$edx = 0x2337" "set edx for bmi test"
 
 if {[record_full_function "bmi"] == true} {
 
+    test_one_general_register "bzhi" "r8" "0xe884173"
+    test_one_general_register "bzhi" "r8" "0x0" "Larger registers"
+
+    test_one_general_register "shrx" "ecx" "0xe884173"
+    test_one_general_register "shlx" "ebx" "0x0"
+    test_one_general_register "sarx" "eax" "0x3"
+    test_one_general_register "rorx" "ebx" "0x3b"
+    test_one_general_register "pext" "ebx" "0x0"
+    test_one_general_register "pdep" "ebx" "0x0"
+
+    test_one_general_register "mulx" "ecx" "0x0"
+    test_one_general_register "mulx" "ebx" "0x0"
+
     test_one_general_register "tzcnt" "r8" "0x3e"
     test_one_general_register "tzcnt" "ebx" "0xe"
     test_one_general_register "tzcnt" "ecx" "0x1e"