From 014d4639d8ca98382886d89aa445444ca6b59c21 Mon Sep 17 00:00:00 2001
From: Anton Korobeynikov <asl@math.spbu.ru>
Date: Thu, 16 Jul 2009 14:13:24 +0000
Subject: [PATCH] 32 bit shifts have only 12 bit displacements

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76000 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/SystemZ/SystemZISelDAGToDAG.cpp | 16 ++++++++++---
 lib/Target/SystemZ/SystemZInstrInfo.td     |  2 +-
 lib/Target/SystemZ/SystemZOperands.td      |  2 +-
 test/CodeGen/SystemZ/2009-07-04-Shl32.ll   | 27 ++++++++++++++++++++++
 4 files changed, 42 insertions(+), 5 deletions(-)
 create mode 100644 test/CodeGen/SystemZ/2009-07-04-Shl32.ll

diff --git a/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp b/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
index fb0c5dc42d3..e009eec48b1 100644
--- a/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
+++ b/lib/Target/SystemZ/SystemZISelDAGToDAG.cpp
@@ -114,8 +114,11 @@ namespace {
     #include "SystemZGenDAGISel.inc"
 
   private:
+    bool SelectAddrRI12Only(SDValue Op, SDValue& Addr,
+                            SDValue &Base, SDValue &Disp);
     bool SelectAddrRI12(SDValue Op, SDValue& Addr,
-                        SDValue &Base, SDValue &Disp);
+                        SDValue &Base, SDValue &Disp,
+                        bool is12BitOnly = false);
     bool SelectAddrRI(SDValue Op, SDValue& Addr,
                       SDValue &Base, SDValue &Disp);
     bool SelectAddrRRI12(SDValue Op, SDValue Addr,
@@ -346,8 +349,14 @@ void SystemZDAGToDAGISel::getAddressOperands(const SystemZRRIAddressMode &AM,
 
 /// Returns true if the address can be represented by a base register plus
 /// an unsigned 12-bit displacement [r+imm].
+bool SystemZDAGToDAGISel::SelectAddrRI12Only(SDValue Op, SDValue& Addr,
+                                             SDValue &Base, SDValue &Disp) {
+  return SelectAddrRI12(Op, Addr, Base, Disp, /*is12BitOnly*/true);
+}
+
 bool SystemZDAGToDAGISel::SelectAddrRI12(SDValue Op, SDValue& Addr,
-                                         SDValue &Base, SDValue &Disp) {
+                                         SDValue &Base, SDValue &Disp,
+                                         bool is12BitOnly) {
   SystemZRRIAddressMode AM20(/*isRI*/true), AM12(/*isRI*/true);
   bool Done = false;
 
@@ -373,7 +382,8 @@ bool SystemZDAGToDAGISel::SelectAddrRI12(SDValue Op, SDValue& Addr,
     return false;
 
   // Check, whether we can match stuff using 20-bit displacements
-  if (!Done && !MatchAddress(Addr, AM20, /* is12Bit */ false))
+  if (!Done && !is12BitOnly &&
+      !MatchAddress(Addr, AM20, /* is12Bit */ false))
     if (AM12.Disp == 0 && AM20.Disp != 0)
       return false;
 
diff --git a/lib/Target/SystemZ/SystemZInstrInfo.td b/lib/Target/SystemZ/SystemZInstrInfo.td
index 0c0c30bd6d2..8a616c5764e 100644
--- a/lib/Target/SystemZ/SystemZInstrInfo.td
+++ b/lib/Target/SystemZ/SystemZInstrInfo.td
@@ -652,7 +652,7 @@ def ROTL64ri  : Pseudo<(outs GR64:$dst), (ins GR64:$src, i32imm:$amt),
                        [(set GR64:$dst, (rotl GR64:$src, (i32 imm:$amt)))]>;
 
 //===----------------------------------------------------------------------===//
-// Test instructions (like AND but do not produce any result
+// Test instructions (like AND but do not produce any result)
 
 // Integer comparisons
 let Defs = [PSW] in {
diff --git a/lib/Target/SystemZ/SystemZOperands.td b/lib/Target/SystemZ/SystemZOperands.td
index 495a9d5d564..d783050358d 100644
--- a/lib/Target/SystemZ/SystemZOperands.td
+++ b/lib/Target/SystemZ/SystemZOperands.td
@@ -252,7 +252,7 @@ def s32imm64 : Operand<i64> {
 
 // riaddr := reg + imm
 def riaddr32 : Operand<i32>,
-               ComplexPattern<i32, 2, "SelectAddrRI12", []> {
+               ComplexPattern<i32, 2, "SelectAddrRI12Only", []> {
   let PrintMethod = "printRIAddrOperand";
   let MIOperandInfo = (ops ADDR32:$base, u12imm:$disp);
 }
diff --git a/test/CodeGen/SystemZ/2009-07-04-Shl32.ll b/test/CodeGen/SystemZ/2009-07-04-Shl32.ll
new file mode 100644
index 00000000000..8547ec3314a
--- /dev/null
+++ b/test/CodeGen/SystemZ/2009-07-04-Shl32.ll
@@ -0,0 +1,27 @@
+; RUN: llvm-as < %s | llc
+
+target datalayout = "E-p:64:64:64-i8:8:16-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f128:128:128-a0:16:16"
+target triple = "s390x-linux"
+
+define void @compdecomp(i8* nocapture %data, i64 %data_len) nounwind {
+entry:
+	br label %for.body38
+
+for.body38:		; preds = %for.body38, %entry
+	br i1 undef, label %for.cond220, label %for.body38
+
+for.cond220:		; preds = %for.cond220, %for.body38
+	br i1 false, label %for.cond220, label %for.end297
+
+for.end297:		; preds = %for.cond220
+	%tmp334 = load i8* undef		; <i8> [#uses=1]
+	%conv343 = zext i8 %tmp334 to i32		; <i32> [#uses=1]
+	%sub344 = add i32 %conv343, -1		; <i32> [#uses=1]
+	%shl345 = shl i32 1, %sub344		; <i32> [#uses=1]
+	%conv346 = sext i32 %shl345 to i64		; <i64> [#uses=1]
+	br label %for.body356
+
+for.body356:		; preds = %for.body356, %for.end297
+	%mask.1633 = phi i64 [ %conv346, %for.end297 ], [ undef, %for.body356 ]		; <i64> [#uses=0]
+	br label %for.body356
+}
-- 
2.34.1