[llvm] [RISCV] Make All VType Parts Optional (PR #144971)

[Sam Elliott via llvm-commits]

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@@ -1,12 +1,6 @@
 # RUN: not llvm-mc -triple=riscv64 --mattr=+v --mattr=+f %s 2>&1 \
 # RUN:        | FileCheck %s --check-prefix=CHECK-ERROR
 
-vsetivli a2, 32, e8,m1
-# CHECK-ERROR: operand must be e[8|16|32|64],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
-
-vsetivli a2, zero, e8,m1
-# CHECK-ERROR: operand must be e[8|16|32|64],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
-
 vsetivli a2, 5, (1 << 10)
 # CHECK-ERROR: operand must be e[8|16|32|64],m[1|2|4|8|f2|f4|f8],[ta|tu],[ma|mu]
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lenary wrote:

I honestly thought that trying to make it clear which bits are optional and which aren't with sort-of regex syntax would be more confusing than the current message. We can certainly look at improving them in the future, but probably by entirely revisiting how error messages are generated. 

https://github.com/llvm/llvm-project/pull/144971