[LoopVectorizer] Use two step casting for float to pointer types.

Summary:
LoopVectorizer is creating casts between vec<ptr> and vec<float> types
on ARM when compiling OpenCV. Since, tIs is illegal to directly cast a
floating point type to a pointer type even if the types have same size
causing a crash. Fix the crash using a two-step casting by bitcasting
to integer and integer to pointer/float.
Fixes PR33804.

Reviewers: mkuper, Ayal, dlj, rengolin, srhines

Reviewed By: rengolin

Subscribers: aemerson, kristof.beyls, mkazantsev, Meinersbur, rengolin, mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D35498

llvm-svn: 312331

1 files changed, 66 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/AArch64/loopvectorize_pr33804_double.ll b/llvm/test/CodeGen/AArch64/loopvectorize_pr33804_double.ll
new file mode 100644
index 00000000000..7468784f38d
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/loopvectorize_pr33804_double.ll
@@ -0,0 +1,66 @@
+; RUN: opt -loop-vectorize -S < %s | FileCheck %s
+
+; These tests check that we don't crash if vectorizer decides to cast
+; a double value to be stored into a pointer type or vice-versa.
+
+; This test checks when a double value is stored into a pointer type.
+
+; ModuleID = 'bugpoint-reduced-simplified.bc'
+source_filename = "bugpoint-output-26dbd81.bc"
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64-unknown-linux-gnu"
+
+%struct.CvNode1D = type { double, %struct.CvNode1D* }
+
+; CHECK-LABEL: @cvCalcEMD2
+; CHECK: vector.body
+; CHECK: store <{{[0-9]+}} x %struct.CvNode1D*>
+define void @cvCalcEMD2() local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
+entry:
+  br label %for.body14.i.i
+
+for.body14.i.i:                                   ; preds = %for.body14.i.i, %entry
+  %i.1424.i.i = phi i32 [ %inc21.i.i, %for.body14.i.i ], [ 0, %entry ]
+  %arrayidx15.i.i1427 = getelementptr inbounds %struct.CvNode1D, %struct.CvNode1D* undef, i32 %i.1424.i.i
+  %val.i.i = getelementptr inbounds %struct.CvNode1D, %struct.CvNode1D* %arrayidx15.i.i1427, i32 0, i32 0
+  store double 0xC415AF1D80000000, double* %val.i.i, align 4
+  %next19.i.i = getelementptr inbounds %struct.CvNode1D, %struct.CvNode1D* undef, i32 %i.1424.i.i, i32 1
+  store %struct.CvNode1D* undef, %struct.CvNode1D** %next19.i.i, align 4
+  %inc21.i.i = add nuw nsw i32 %i.1424.i.i, 1
+  %exitcond438.i.i = icmp eq i32 %inc21.i.i, 0
+  br i1 %exitcond438.i.i, label %for.end22.i.i, label %for.body14.i.i
+
+for.end22.i.i:                                    ; preds = %for.body14.i.i
+  unreachable
+}
+
+; This test checks when a pointer value is stored into a double type.
+
+%struct.CvNode1D2 = type { %struct.CvNode1D2*, double }
+
+; CHECK-LABEL: @cvCalcEMD2_2
+; CHECK: vector.body
+; CHECK: store <{{[0-9]+}} x double>
+define void @cvCalcEMD2_2() local_unnamed_addr #0 personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
+entry:
+  br label %for.body14.i.i
+
+for.body14.i.i:                                   ; preds = %for.body14.i.i, %entry
+  %i.1424.i.i = phi i32 [ %inc21.i.i, %for.body14.i.i ], [ 0, %entry ]
+  %next19.i.i = getelementptr inbounds %struct.CvNode1D2, %struct.CvNode1D2* undef, i32 %i.1424.i.i, i32 0
+  store %struct.CvNode1D2* undef, %struct.CvNode1D2** %next19.i.i, align 4
+  %arrayidx15.i.i1427 = getelementptr inbounds %struct.CvNode1D2, %struct.CvNode1D2* undef, i32 %i.1424.i.i
+  %val.i.i = getelementptr inbounds %struct.CvNode1D2, %struct.CvNode1D2* %arrayidx15.i.i1427, i32 0, i32 1
+  store double 0xC415AF1D80000000, double* %val.i.i, align 4
+  %inc21.i.i = add nuw nsw i32 %i.1424.i.i, 1
+  %exitcond438.i.i = icmp eq i32 %inc21.i.i, 0
+  br i1 %exitcond438.i.i, label %for.end22.i.i, label %for.body14.i.i
+
+for.end22.i.i:                                    ; preds = %for.body14.i.i
+  unreachable
+}
+
+declare i32 @__gxx_personality_v0(...)
+
+attributes #0 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
+