[llvm] [AMDGPU] Add AMDGPU specific variadic operation MCExprs (PR #82022)

[Matt Arsenault via llvm-commits]

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+// RUN: not llvm-mc -triple amdgcn-amd-amdhsa %s 2>&1 | FileCheck --check-prefix=ASM %s
+
+.set one, 1
+.set two, 2
+.set three, 3
+
+.set max_empty, max()
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: empty max expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set or_empty, or()
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: empty or expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_post_aux_comma, max(one,)
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: mismatch of commas in max expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_pre_aux_comma, max(,one)
+// asm: :[[@line-1]]:{{[0-9]+}}: error: unknown token in expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_double_comma, max(one,, two)
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: unknown token in expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_no_comma, max(one two)
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: unexpected token in max expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_missing_paren, max(two
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: unexpected token in max expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set max_expression_one, max(three, four,
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: unknown token in expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
+.set or_expression_one, or(four, five
+// ASM: :[[@LINE-1]]:{{[0-9]+}}: error: unexpected token in or expression
+// ASM: :[[@LINE-2]]:{{[0-9]+}}: error: missing expression
+
----------------
arsenm wrote:

Check attempt to use with no parens 

https://github.com/llvm/llvm-project/pull/82022