Add .dword direcrive support for aarch64 mc

[raj.khem]

Summary

.dword is used in many packages in linux world. The last I run into is klibc.

[rengolin]

dword is indeed widely used. I'm surprised we didn't support that yet. Apparently, neither does Arm, only X86, Mips and RiscV.

[raj.khem]

@rengolin who can help committing this patch ?

[ostannard]

A patch adding the same functionality was added back in May: D61719, rL360381.

Reviewers tend to assume that patch authors have commit access, if you don't then just say so when the patch is accepted and the reviewer will commit it for you.

[raj.khem]

In D57529#1697029, @ostannard wrote:

A patch adding the same functionality was added back in May: D61719, rL360381.

Reviewers tend to assume that patch authors have commit access, if you don't then just say so when the patch is accepted and the reviewer will commit it for you.

thanks, as long as the issues are fixed this is fine.

llvm/lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp

 
     // Alias .hword/.word/xword to the target-independent .2byte/.4byte/.8byte
     // directives as they have the same form and semantics:
-    ///  ::= (.hword | .word | .xword ) [ expression (, expression)* ]
+    ///  ::= (.hword | .word | .xword | .dword ) [ expression (, expression)* ]
     Parser.addAliasForDirective(".hword", ".2byte");
     Parser.addAliasForDirective(".word", ".4byte");
     Parser.addAliasForDirective(".xword", ".8byte");
+    Parser.addAliasForDirective(".dword", ".8byte");
 
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(getSTI().getFeatureBits()));

llvm/test/MC/AArch64/data-directives-invalid.s

+# RUN: not llvm-mc -triple aarch64 < %s 2>&1 | FileCheck %s
+
+# CHECK: [[@LINE+1]]:8: error: out of range literal value in '.hword' directive
+.hword 0xffffa
+# CHECK: [[@LINE+1]]:8: error: out of range literal value in '.2byte' directive
+.2byte 0xffffa
+# CHECK: [[@LINE+1]]:7: error: out of range literal value in '.word' directive
+.word 0xffffffffa
+# CHECK: [[@LINE+1]]:8: error: out of range literal value in '.4byte' directive
+.4byte 0xffffffffa
+# CHECK: [[@LINE+1]]:8: error: literal value out of range for directive in '.dword' directive
+.dword 0xffffffffffffffffa
+# CHECK: [[@LINE+1]]:8: error: literal value out of range for directive in '.xword' directive
+.xword 0xffffffffffffffffa
+# CHECK: [[@LINE+1]]:8: error: literal value out of range for directive in '.8byte' directive
+.8byte 0xffffffffffffffffa