[InstCombine] Transform !range metadata to !nonnull when combining loads

When combining an integer load with !range metadata that does not include 0 to a pointer load, make sure emit !nonnull metadata on the newly-created pointer load. This prevents the !nonnull metadata from being dropped during a ptrtoint/inttoptr pair.

This fixes PR30597.

Patch by Ariel Ben-Yehuda!

Differential Revision: https://reviews.llvm.org/D25215

llvm-svn: 283836

1 files changed, 32 insertions, 0 deletions

diff --git a/llvm/test/Transforms/InstCombine/PR30597.ll b/llvm/test/Transforms/InstCombine/PR30597.ll
new file mode 100644
index 00000000000..c0803ed7120
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/PR30597.ll
@@ -0,0 +1,32 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: readonly uwtable
+define i1 @dot_ref_s(i32** noalias nocapture readonly dereferenceable(8)) {
+entry-block:
+  %loadedptr = load i32*, i32** %0, align 8, !nonnull !0
+  %ptrtoint = ptrtoint i32* %loadedptr to i64
+  %inttoptr = inttoptr i64 %ptrtoint to i32*
+  %switchtmp = icmp eq i32* %inttoptr, null
+  ret i1 %switchtmp
+
+; CHECK-LABEL: @dot_ref_s
+; CHECK-NEXT: entry-block:
+; CHECK-NEXT: ret i1 false
+}
+
+; Function Attrs: readonly uwtable
+define i64* @function(i64* noalias nocapture readonly dereferenceable(8)) {
+entry-block:
+  %loaded = load i64, i64* %0, align 8, !range !1
+  %inttoptr = inttoptr i64 %loaded to i64*
+  ret i64* %inttoptr
+; CHECK-LABEL: @function
+; CHECK: %{{.+}} = load i64*, i64** %{{.+}}, align 8, !nonnull
+}
+
+
+!0 = !{}
+!1 = !{i64 1, i64 140737488355327}