[ConstantFold] Disallow folding vector geps into bitcasts
Summary:
Getelementptr returns a vector of pointers, instead of a single address,
when one or more of its arguments is a vector. In such case it is not
possible to simplify the expression by inserting a bitcast of operand(0)
into the destination type, as it will create a bitcast between different
sizes.
Reviewers: majnemer, mkuper, mssimpso, spatel
Reviewed By: spatel
Subscribers: lebedev.ri, llvm-commits
Differential Revision: https://reviews.llvm.org/D46379
llvm-svn: 333783
diff --git a/llvm/test/Analysis/ConstantFolding/gep-zeroinit-vector.ll b/llvm/test/Analysis/ConstantFolding/gep-zeroinit-vector.ll
index da8cbcd..bb5fcbd 100644
--- a/llvm/test/Analysis/ConstantFolding/gep-zeroinit-vector.ll
+++ b/llvm/test/Analysis/ConstantFolding/gep-zeroinit-vector.ll
@@ -1,15 +1,15 @@
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -constprop -S -o - | FileCheck %s
-; Testcase that point out faulty bitcast that cast between different sizes.
-; See "bitcast ([1 x %rec8]* @a to <2 x i16*>)" in checks below
+; Testcase that verify that we don't get a faulty bitcast that cast between
+; different sizes.
%rec8 = type { i16 }
@a = global [1 x %rec8] zeroinitializer
define <2 x i16*> @test_gep() {
; CHECK-LABEL: @test_gep(
-; CHECK-NEXT: ret <2 x i16*> bitcast ([1 x %rec8]* @a to <2 x i16*>)
+; CHECK-NEXT: ret <2 x i16*> <i16* getelementptr inbounds (%rec8, %rec8* extractelement (<2 x %rec8*> getelementptr ([1 x %rec8], [1 x %rec8]* @a, <2 x i64> zeroinitializer, <2 x i64> zeroinitializer), i32 0), i32 0, i32 0), i16* getelementptr inbounds (%rec8, %rec8* extractelement (<2 x %rec8*> getelementptr ([1 x %rec8], [1 x %rec8]* @a, <2 x i64> zeroinitializer, <2 x i64> zeroinitializer), i32 1), i32 0, i32 0)>
;
%A = getelementptr [1 x %rec8], [1 x %rec8]* @a, <2 x i16> zeroinitializer, <2 x i64> zeroinitializer
%B = bitcast <2 x %rec8*> %A to <2 x i16*>