From d51f7b3b43233aae3bbe1479ca221f13c85b147a Mon Sep 17 00:00:00 2001
From: Krzysztof Parzyszek <kparzysz@codeaurora.org>
Date: Thu, 30 Aug 2018 22:26:43 +0000
Subject: [PATCH] [Hexagon] Check validity of register class when generating
 bitsplit

llvm-svn: 341137
---
 llvm/lib/Target/Hexagon/HexagonBitSimplify.cpp     |  4 +++
 llvm/test/CodeGen/Hexagon/bit-bitsplit-regclass.ll | 40 ++++++++++++++++++++++
 2 files changed, 44 insertions(+)
 create mode 100644 llvm/test/CodeGen/Hexagon/bit-bitsplit-regclass.ll

diff --git a/llvm/lib/Target/Hexagon/HexagonBitSimplify.cpp b/llvm/lib/Target/Hexagon/HexagonBitSimplify.cpp
index 61675fd..1bdebe5 100644
--- a/llvm/lib/Target/Hexagon/HexagonBitSimplify.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonBitSimplify.cpp
@@ -2227,6 +2227,10 @@ bool BitSimplification::genBitSplit(MachineInstr *MI,
   for (unsigned S = AVs.find_first(); S; S = AVs.find_next(S)) {
     // The number of leading zeros here should be the number of trailing
     // non-zeros in RC.
+    unsigned SRC = MRI.getRegClass(S)->getID();
+    if (SRC != Hexagon::IntRegsRegClassID &&
+        SRC != Hexagon::DoubleRegsRegClassID)
+      continue;
     if (!BT.has(S))
       continue;
     const BitTracker::RegisterCell &SC = BT.lookup(S);
diff --git a/llvm/test/CodeGen/Hexagon/bit-bitsplit-regclass.ll b/llvm/test/CodeGen/Hexagon/bit-bitsplit-regclass.ll
new file mode 100644
index 0000000..57f7c86
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/bit-bitsplit-regclass.ll
@@ -0,0 +1,40 @@
+; RUN: llc -march=hexagon -hexagon-initial-cfg-cleanup=0 < %s | FileCheck %s
+
+; Check for successful compilation.
+; CHECK: r{{[0-9]+}} = insert(r{{[0-9]+}},#1,#31)
+
+; This cannot be a .mir test, because the failure depends on ordering of
+; virtual registers, and the .mir loader renumbers them in a way that hides
+; the problem.
+
+target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048"
+target triple = "hexagon"
+
+; Function Attrs: nounwind
+define void @f0() #0 align 2 {
+b0:
+  br label %b1
+
+b1:                                               ; preds = %b3, %b0
+  %v0 = phi i64 [ 0, %b0 ], [ %v6, %b3 ]
+  br i1 undef, label %b2, label %b3
+
+b2:                                               ; preds = %b1
+  br label %b3
+
+b3:                                               ; preds = %b2, %b1
+  %v1 = phi i64 [ undef, %b2 ], [ %v0, %b1 ]
+  %v2 = and i64 %v1, 1
+  %v3 = trunc i64 %v2 to i32
+  %v4 = tail call i32 @llvm.hexagon.C2.mux(i32 %v3, i32 undef, i32 undef)
+  %v5 = trunc i32 %v4 to i8
+  store i8 %v5, i8* undef, align 1
+  %v6 = lshr i64 %v1, 1
+  br label %b1
+}
+
+; Function Attrs: nounwind readnone
+declare i32 @llvm.hexagon.C2.mux(i32, i32, i32) #1
+
+attributes #0 = { nounwind "target-cpu"="hexagonv60" }
+attributes #1 = { nounwind readnone }
-- 
2.7.4