[clang] [llvm] [AArch64][SVE] Change the immediate argument in svextq (PR #115340)

[via cfe-commits]

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@@ -2286,7 +2286,7 @@ let SVETargetGuard = "sve2p1", SMETargetGuard = InvalidMode in {
   def SVTBLQ : SInst<"svtblq[_{d}]", "ddu", "cUcsUsiUilUlbhfd", MergeNone, "aarch64_sve_tblq">;
   def SVTBXQ : SInst<"svtbxq[_{d}]", "dddu", "cUcsUsiUilUlbhfd", MergeNone, "aarch64_sve_tbxq">;
   // EXTQ
-  def EXTQ : SInst<"svextq[_{d}]", "dddk", "cUcsUsiUilUlbhfd", MergeNone, "aarch64_sve_extq", [], [ImmCheck<2, ImmCheck0_15>]>;
+  def EXTQ : SInst<"svextq[_{d}]", "dddk", "cUcsUsiUilUlbhfd", MergeNone, "aarch64_sve_extq", [], [ImmCheck<2, ImmCheckLaneIndex, 0>]>;
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CarolineConcatto wrote:

I believe what we want here is something like svext:
def SVEXT        : SInst<"svext[_{d}]",       "dddi", "csilUcUsUiUlhfd", MergeNone, "aarch64_sve_ext", [VerifyRuntimeMode], [ImmCheck<2, ImmCheckExtract, 1>]>;
The current Immediate I don't believe applies here, because in this case we need to scale the immediate to bytes. Like it was done for svext
https://developer.arm.com/architectures/instruction-sets/intrinsics/#f:@navigationhierarchiesreturnbasetype=[%5Buint,int%5D]&q=svext

https://github.com/llvm/llvm-project/pull/115340