[InstCombine] Add reduced test for PR 71330; NFC

Author: goldsteinn

llvm/test/Transforms/InstCombine/pr71330.ll

@@ -0,0 +1,77 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=instcombine -S < %s | FileCheck %s
+
+define void @pr71330(i32 %conv, i1 %tobool19.not4, i16 %lb) {
+; CHECK-LABEL: define void @pr71330(
+; CHECK-SAME: i32 [[CONV:%.*]], i1 [[TOBOOL19_NOT4:%.*]], i16 [[LB:%.*]]) {
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    br label [[FOR_COND7_PREHEADER:%.*]]
+; CHECK:       for.cond7.preheader:
+; CHECK-NEXT:    br i1 [[TOBOOL19_NOT4]], label [[FOR_COND7_PREHEADER_SPLIT_US:%.*]], label [[FOR_COND7:%.*]]
+; CHECK:       for.cond7.preheader.split.us:
+; CHECK-NEXT:    br i1 true, label [[FOR_COND7_PREHEADER_SPLIT_US_SPLIT:%.*]], label [[FOR_COND7_US_US:%.*]]
+; CHECK:       for.cond7.us.us:
+; CHECK-NEXT:    br i1 poison, label [[FOR_COND7_US_US]], label [[FOR_END25:%.*]]
+; CHECK:       for.cond7.preheader.split.us.split:
+; CHECK-NEXT:    ret void
+; CHECK:       for.cond7:
+; CHECK-NEXT:    [[ADD9:%.*]] = add i32 [[CONV]], 3
+; CHECK-NEXT:    [[CMP12:%.*]] = icmp slt i32 [[ADD9]], 0
+; CHECK-NEXT:    br i1 [[CMP12]], label [[FOR_BODY14:%.*]], label [[FOR_END25]]
+; CHECK:       for.body14:
+; CHECK-NEXT:    ret void
+; CHECK:       for.end25:
+; CHECK-NEXT:    br i1 false, label [[FOR_COND7_PREHEADER]], label [[FOR_END36:%.*]]
+; CHECK:       for.end36:
+; CHECK-NEXT:    ret void
+;
+entry:
+  br label %for.cond7.preheader
+
+for.cond7.preheader:  ; preds = %for.end25, %entry
+  %storemerge33 = phi i32 [ -3, %entry ], [ 0, %for.end25 ]
+  %sm8 = and i32 %storemerge33, 1
+  %add = add i32 %storemerge33, 8
+  %cmp.i.i.not = icmp eq i32 %sm8, 0
+  %cmp3.i.i = icmp eq i32 %add, 0
+  %and7.i.i = and i32 %storemerge33, 1
+  %cmp8.i.i = icmp eq i32 %and7.i.i, 0
+  %tobool.not.i.i = icmp eq i32 %add, 0
+  %..i.i = select i1 %tobool.not.i.i, i32 1, i32 3
+  br i1 %tobool19.not4, label %for.cond7.preheader.split.us, label %for.cond7
+
+for.cond7.preheader.split.us:  ; preds = %for.cond7.preheader
+  br i1 %cmp.i.i.not, label %for.cond7.us.us, label %for.cond7.preheader.split.us.split
+
+for.cond7.us.us:  ; preds = %for.cond7.us.us, %for.cond7.preheader.split.us
+  %spec.select = select i1 %cmp8.i.i, i32 1, i32 %..i.i
+  %retval.0.i.i.us.us = select i1 %cmp3.i.i, i32 0, i32 %spec.select
+  %add9.us.us = add i32 %retval.0.i.i.us.us, %conv
+  %conv10.us.us = sext i32 %add9.us.us to i64
+  %cmp12.us.us = icmp slt i64 %conv10.us.us, 0
+  br i1 %cmp12.us.us, label %for.cond7.us.us, label %for.end25
+
+for.cond7.preheader.split.us.split:  ; preds = %for.cond7.preheader.split.us
+  ret void
+
+for.cond7:  ; preds = %for.cond7.preheader
+  %cmp.i.i.not.not = xor i1 %cmp.i.i.not, true
+  %brmerge = select i1 %cmp.i.i.not.not, i1 true, i1 %cmp3.i.i
+  %spec.select34 = select i1 %cmp8.i.i, i32 1, i32 %..i.i
+  %retval.0.i.i = select i1 %brmerge, i32 0, i32 %spec.select34
+  %add9 = add i32 %retval.0.i.i, %conv
+  %conv10 = sext i32 %add9 to i64
+  %cmp12 = icmp slt i64 %conv10, 0
+  br i1 %cmp12, label %for.body14, label %for.end25
+
+for.body14:  ; preds = %for.cond7
+  ret void
+
+for.end25:  ; preds = %for.cond7, %for.cond7.us.us
+  %conv35 = zext i16 %lb to i32
+  %cmp = icmp slt i32 %conv35, 0
+  br i1 %cmp, label %for.cond7.preheader, label %for.end36
+
+for.end36:  ; preds = %for.end25
+  ret void
+}