From 802679e4f8362d3c819b83223854c638cc8f2b7f Mon Sep 17 00:00:00 2001
From: iximeow <me@iximeow.net>
Date: Sat, 22 Feb 2020 15:38:41 -0800
Subject: fix {jmp,call} <reg>, as well as jmpf/callf

also support vmxon to finish out the f30f opcode map

add tests for forms of inc/dec, as well as TODOs, as yaxpeax-x86 doesn't
provide a way to distinguish different operand sizes (yet)
---
 src/long_mode/display.rs |  2 ++
 src/long_mode/mod.rs     | 26 ++++++++++++++++++++++++++
 test/test.rs             | 17 +++++++++++++++++
 3 files changed, 45 insertions(+)

diff --git a/src/long_mode/display.rs b/src/long_mode/display.rs
index d45a98a..3025c16 100644
--- a/src/long_mode/display.rs
+++ b/src/long_mode/display.rs
@@ -652,6 +652,7 @@ impl fmt::Display for Opcode {
             &Opcode::BLSMSK => write!(f, "blsmsk"),
             &Opcode::BLSR => write!(f, "blsr"),
             &Opcode::VMCLEAR => write!(f, "vmclear"),
+            &Opcode::VMXON => write!(f, "vmxon"),
             &Opcode::VMCALL => write!(f, "vmcall"),
             &Opcode::VMLAUNCH => write!(f, "vmlaunch"),
             &Opcode::VMRESUME => write!(f, "vmresume"),
@@ -1855,6 +1856,7 @@ impl <T: fmt::Write, Color: fmt::Display, Y: YaxColors<Color>> Colorize<T, Color
             Opcode::VMREAD |
             Opcode::VMWRITE |
             Opcode::VMCLEAR |
+            Opcode::VMXON |
             Opcode::VMCALL |
             Opcode::VMLAUNCH |
             Opcode::VMRESUME |
diff --git a/src/long_mode/mod.rs b/src/long_mode/mod.rs
index 79e5b39..73570c1 100644
--- a/src/long_mode/mod.rs
+++ b/src/long_mode/mod.rs
@@ -659,6 +659,7 @@ pub enum Opcode {
     BLSMSK,
     BLSR,
     VMCLEAR,
+    VMXON,
     VMCALL,
     VMLAUNCH,
     VMRESUME,
@@ -5111,6 +5112,13 @@ fn read_operands<T: Iterator<Item=u8>>(decoder: &InstDecoder, mut bytes_iter: T,
                 Opcode::PUSH,
                 Opcode::Invalid
             ][((modrm >> 3) & 7) as usize];
+            if instruction.operands[0] == OperandSpec::RegMMM {
+                if opcode == Opcode::CALL || opcode == Opcode::JMP {
+                    instruction.modrm_mmm.bank = RegisterBank::Q;
+                } else if opcode == Opcode::CALLF || opcode == Opcode::JMPF {
+                    return Err(DecodeError::InvalidOperand);
+                }
+            }
             instruction.opcode = opcode;
             instruction.operand_count = 1;
         }
@@ -5643,6 +5651,24 @@ fn unlikely_operands<T: Iterator<Item=u8>>(decoder: &InstDecoder, mut bytes_iter
                 }
             }
         },
+        OperandCode::ModRM_0xf30fc7 => {
+            let modrm = read_modrm(&mut bytes_iter, length)?;
+
+            let r = (modrm >> 3) & 7;
+            match r {
+                6 => {
+                    instruction.opcode = Opcode::VMXON;
+                    instruction.operands[0] = read_E(&mut bytes_iter, instruction, modrm, 1 /* doesn't matter, something using this width is invalid */, length)?;
+                    if instruction.operands[0] == OperandSpec::RegMMM {
+                        return Err(DecodeError::InvalidOperand);
+                    }
+                    instruction.operand_count = 1;
+                }
+                _ => {
+                    return Err(DecodeError::InvalidOpcode);
+                }
+            }
+        },
         OperandCode::G_mm_Edq => {
             instruction.operands[1] = mem_oper;
             instruction.modrm_rrr.bank = RegisterBank::MM;
diff --git a/test/test.rs b/test/test.rs
index fe6a898..28263ae 100644
--- a/test/test.rs
+++ b/test/test.rs
@@ -747,6 +747,11 @@ fn test_control_flow() {
     test_display(&[0x74, 0x47], "jz 0x47");
     test_display(&[0xff, 0x15, 0x7e, 0x72, 0x24, 0x00], "call [rip + 0x24727e]");
     test_display(&[0xff, 0x24, 0xcd, 0x70, 0xa0, 0xbc, 0x01], "jmp [rcx * 8 + 0x1bca070]");
+    test_display(&[0xff, 0xe0], "jmp rax");
+    test_display(&[0x66, 0xff, 0xe0], "jmp rax");
+    test_display(&[0x67, 0xff, 0xe0], "jmp rax");
+    test_invalid(&[0xff, 0xd8]);
+    test_display(&[0xff, 0x18], "callf [rax]");
     test_display(&[0xc3], "ret");
 }
 
@@ -772,6 +777,9 @@ fn test_bmi1() {
     let no_bmi1 = InstDecoder::minimal();
     test_display_under(&bmi1, &[0x41, 0x0f, 0xbc, 0xd3], "tzcnt edx, r11d");
     test_display_under(&no_bmi1, &[0x41, 0x0f, 0xbc, 0xd3], "bsf edx, r11d");
+
+    test_display_under(&bmi1, &[0xf3, 0x0f, 0xb8, 0xc1], "popcnt eax, ecx");
+    test_display_under(&bmi1, &[0xf3, 0x4f, 0x0f, 0xb8, 0xc1], "popcnt r8, r9");
 }
 
 #[test]
@@ -783,6 +791,13 @@ fn test_bitwise() {
 
 #[test]
 fn test_misc() {
+    // TODO
+//    test_display(&[0xf2, 0x0f, 0x38, 0xf0, 0xc1], "crc32 eax, cl");
+//    test_display(&[0xf2, 0x0f, 0x38, 0xf1, 0xc1], "crc32 eax, ecx");
+    test_display(&[0xfe, 0x00], "inc [rax]"); // TODO: inc byte [rax]
+    test_display(&[0xfe, 0x08], "dec [rax]"); // TODO: dec byte [rax]
+    test_display(&[0xff, 0x00], "inc [rax]"); // TODO: inc dword [rax]
+    test_display(&[0x48, 0xff, 0x00], "inc [rax]"); // TODO: inc qword [rax]
     test_display(&[0xe4, 0x99], "in al, 0x99");
     test_display(&[0xe5, 0x99], "in eax, 0x99");
     test_display(&[0x67, 0xe5, 0x99], "in eax, 0x99");
@@ -815,6 +830,8 @@ fn test_misc() {
     // test_invalid(&[0x66, 0x0f, 0xc7, 0x03]);
     test_display(&[0x66, 0x4f, 0x0f, 0xc7, 0x33], "vmclear [r11]");
     test_display(&[0x66, 0x0f, 0xc7, 0x33], "vmclear [rbx]");
+    test_display(&[0xf3, 0x4f, 0x0f, 0xc7, 0x33], "vmxon [r11]");
+    test_display(&[0xf3, 0x0f, 0xc7, 0x33], "vmxon [rbx]");
 }
 
 #[test]
-- 
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