[llvm] Update the base and index value for masked gather (PR #130920)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,210 @@
+; RUN: llc  -mtriple=x86_64-unknown-unknown -mattr=+avx512f,+avx512bw,+avx512vl,+avx512dq -mcpu=znver5 < %s | FileCheck %s
+; RUN: llc -update-baseIndex -mtriple=x86_64-unknown-unknown -mattr=+avx512f,+avx512bw,+avx512vl,+avx512dq -mcpu=znver5 < %s | FileCheck %s
+; RUN: llc -update-baseIndex=false -mtriple=x86_64-unknown-unknown -mattr=+avx512f,+avx512bw,+avx512vl,+avx512dq -mcpu=znver5 < %s | FileCheck %s -check-prefix=OLD
+
+; ModuleID = 'qwdemo.c'
+source_filename = "qwdemo.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+%struct.pt = type { float, float, float, i32 }
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RKSimon wrote:

this test needs to be reduced down a lot - remove all the unnecessary attributes etc. and just contain the minimal IR to show the problem

https://github.com/llvm/llvm-project/pull/130920