[llvm] [VPlan][LV] Fix invalid truncation in VPScalarIVStepsRecipe (PR #137832)

[Maryam Moghadas via llvm-commits]

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@@ -0,0 +1,31 @@
+; RUN: opt -passes=loop-vectorize -disable-output -S < %s
+; REQUIRES: asserts
+
+target datalayout = "E-m:a-p:32:32-Fi32-i64:64-n32"
+target triple = "powerpc-ibm-aix7.2.0.0"
+
+define void @__power_mod_NMOD_power_init(ptr %a, ptr %b, i32 %n) {
+entry:
+  br label %loop_entry
+
+loop_exit:                                        ; preds = %loop_header
+  br label %loop_entry
+
+loop_entry:                                       ; preds = %loop_exit, %entry
+  %sum.0 = phi double [ 0.000000e+00, %entry ], [ %sum.1, %loop_exit ]
+  %x = load double, ptr %a, align 8
+  br label %loop_header
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maryammo wrote:

I updated the test to use a single loop. 

https://github.com/llvm/llvm-project/pull/137832