Remove cast support for vector registers, and improve error tests

Author: ericastor

llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp

@@ -2595,14 +2595,8 @@ uint16_t RegSizeInBits(const MCRegisterInfo &MRI, MCRegister RegNo) {
     return 64;
   if (X86MCRegisterClasses[X86::RFP80RegClassID].contains(RegNo))
     return 80;
-  if (X86MCRegisterClasses[X86::VR128RegClassID].contains(RegNo) ||
-      X86MCRegisterClasses[X86::VR128XRegClassID].contains(RegNo))
-    return 128;
-  if (X86MCRegisterClasses[X86::VR256XRegClassID].contains(RegNo))
-    return 256;
-  if (X86MCRegisterClasses[X86::VR512RegClassID].contains(RegNo))
-    return 512;
-  llvm_unreachable("Register without known register class");
+  // Unknown register size
+  return 0;
 }
 
 bool X86AsmParser::parseIntelOperand(OperandVector &Operands, StringRef Name) {
@@ -2639,6 +2633,12 @@ bool X86AsmParser::parseIntelOperand(OperandVector &Operands, StringRef Name) {
         // sizes, but not to other types.
         uint16_t RegSize =
             RegSizeInBits(*getContext().getRegisterInfo(), RegNo);
+        if (RegSize == 0)
+          return Error(
+              Start,
+              "cannot cast register '" +
+                  StringRef(getContext().getRegisterInfo()->getName(RegNo)) +
+                  "'; its size is not easily defined.");
         if (RegSize != Size)
           return Error(
               Start,

llvm/test/tools/llvm-ml/cast_errors.asm

@@ -3,39 +3,39 @@
 .code
 
 mov word ptr al, ax
-; CHECK: error: 8-bit register 'AL' cannot be used as a 16-bit WORD
+; CHECK: [[#@LINE-1]]:14: error: 8-bit register 'AL' cannot be used as a 16-bit WORD
 
 mov dword ptr al, eax
-; CHECK: error: 8-bit register 'AL' cannot be used as a 32-bit DWORD
+; CHECK: [[#@LINE-1]]:15: error: 8-bit register 'AL' cannot be used as a 32-bit DWORD
 
 mov qword ptr al, rax
-; CHECK: error: 8-bit register 'AL' cannot be used as a 64-bit QWORD
+; CHECK: [[#@LINE-1]]:15: error: 8-bit register 'AL' cannot be used as a 64-bit QWORD
 
 mov byte ptr ax, al
-; CHECK: error: 16-bit register 'AX' cannot be used as a 8-bit BYTE
+; CHECK: [[#@LINE-1]]:14: error: 16-bit register 'AX' cannot be used as a 8-bit BYTE
 
 mov dword ptr ax, eax
-; CHECK: error: 16-bit register 'AX' cannot be used as a 32-bit DWORD
+; CHECK: [[#@LINE-1]]:15: error: 16-bit register 'AX' cannot be used as a 32-bit DWORD
 
 mov qword ptr ax, rax
-; CHECK: error: 16-bit register 'AX' cannot be used as a 64-bit QWORD
+; CHECK: [[#@LINE-1]]:15: error: 16-bit register 'AX' cannot be used as a 64-bit QWORD
 
 mov byte ptr eax, al
-; CHECK: error: 32-bit register 'EAX' cannot be used as a 8-bit BYTE
+; CHECK: [[#@LINE-1]]:14: error: 32-bit register 'EAX' cannot be used as a 8-bit BYTE
 
 mov word ptr eax, ax
-; CHECK: error: 32-bit register 'EAX' cannot be used as a 16-bit WORD
+; CHECK: [[#@LINE-1]]:14: error: 32-bit register 'EAX' cannot be used as a 16-bit WORD
 
 mov qword ptr eax, rax
-; CHECK: error: 32-bit register 'EAX' cannot be used as a 64-bit QWORD
+; CHECK: [[#@LINE-1]]:15: error: 32-bit register 'EAX' cannot be used as a 64-bit QWORD
 
 mov byte ptr rax, al
-; CHECK: error: 64-bit register 'RAX' cannot be used as a 8-bit BYTE
+; CHECK: [[#@LINE-1]]:14: error: 64-bit register 'RAX' cannot be used as a 8-bit BYTE
 
 mov word ptr rax, ax
-; CHECK: error: 64-bit register 'RAX' cannot be used as a 16-bit WORD
+; CHECK: [[#@LINE-1]]:14: error: 64-bit register 'RAX' cannot be used as a 16-bit WORD
 
 mov dword ptr rax, eax
-; CHECK: error: 64-bit register 'RAX' cannot be used as a 32-bit DWORD
+; CHECK: [[#@LINE-1]]:15: error: 64-bit register 'RAX' cannot be used as a 32-bit DWORD
 
 END