From 1b17614a7283f903363f7c4305da6ea742d3d28b Mon Sep 17 00:00:00 2001
From: Anton Korobeynikov <asl@math.spbu.ru>
Date: Sat, 1 May 2010 12:28:21 +0000
Subject: [PATCH] Do folding for indirect branches, where possible

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102836 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/MSP430/MSP430BranchSelector.cpp |  2 +-
 lib/Target/MSP430/MSP430InstrInfo.td       |  9 +++----
 test/CodeGen/MSP430/indirectbr2.ll         | 29 ++++++++++++++++++++++
 3 files changed, 33 insertions(+), 7 deletions(-)
 create mode 100644 test/CodeGen/MSP430/indirectbr2.ll

diff --git a/lib/Target/MSP430/MSP430BranchSelector.cpp b/lib/Target/MSP430/MSP430BranchSelector.cpp
index 836e4250aba..68cb342b08f 100644
--- a/lib/Target/MSP430/MSP430BranchSelector.cpp
+++ b/lib/Target/MSP430/MSP430BranchSelector.cpp
@@ -157,7 +157,7 @@ bool MSP430BSel::runOnMachineFunction(MachineFunction &Fn) {
           NewSize = 6;
         }
         // Uncond branch to the real destination.
-        I = BuildMI(MBB, I, dl, TII->get(MSP430::B)).addMBB(Dest);
+        I = BuildMI(MBB, I, dl, TII->get(MSP430::Bi)).addMBB(Dest);
 
         // Remove the old branch from the function.
         OldBranch->eraseFromParent();
diff --git a/lib/Target/MSP430/MSP430InstrInfo.td b/lib/Target/MSP430/MSP430InstrInfo.td
index 999364872b3..6b9a2f2f29f 100644
--- a/lib/Target/MSP430/MSP430InstrInfo.td
+++ b/lib/Target/MSP430/MSP430InstrInfo.td
@@ -76,9 +76,6 @@ def memdst : Operand<i16> {
   let MIOperandInfo = (ops GR16, i16imm);
 }
 
-// Branch targets have OtherVT type.
-def brtarget : Operand<OtherVT>;
-
 // Short jump targets have OtherVT type and are printed as pcrel imm values.
 def jmptarget : Operand<OtherVT> {
   let PrintMethod = "printPCRelImmOperand";
@@ -177,9 +174,9 @@ let isBarrier = 1 in {
                    [(br bb:$dst)]>;
   let isIndirectBranch = 1 in {
     // Long branches
-    def B   : I16ri<0, (outs), (ins brtarget:$dst),
-                    "br\t$dst",
-                    []>;
+    def Bi  : I16ri<0, (outs), (ins i16imm:$brdst),
+                    "br\t$brdst",
+                    [(brind tblockaddress:$brdst)]>;
     def Br  : I16rr<0, (outs), (ins GR16:$brdst),
                     "mov.w\t{$brdst, pc}",
                     [(brind GR16:$brdst)]>;
diff --git a/test/CodeGen/MSP430/indirectbr2.ll b/test/CodeGen/MSP430/indirectbr2.ll
new file mode 100644
index 00000000000..93cfb2506bb
--- /dev/null
+++ b/test/CodeGen/MSP430/indirectbr2.ll
@@ -0,0 +1,29 @@
+; RUN: llc -march=msp430 < %s | FileCheck %s
+@C.0.2070 = private constant [5 x i8*] [i8* blockaddress(@foo, %L1), i8* blockaddress(@foo, %L2), i8* blockaddress(@foo, %L3), i8* blockaddress(@foo, %L4), i8* blockaddress(@foo, %L5)] ; <[5 x i8*]*> [#uses=1]
+
+define internal i16 @foo(i16 %i) nounwind {
+entry:
+  %tmp1 = getelementptr inbounds [5 x i8*]* @C.0.2070, i16 0, i16 %i ; <i8**> [#uses=1]
+  %gotovar.4.0 = load i8** %tmp1, align 4        ; <i8*> [#uses=1]
+; CHECK: mov.w   .LC.0.2070(r15), pc
+  indirectbr i8* %gotovar.4.0, [label %L5, label %L4, label %L3, label %L2, label %L1]
+
+L5:                                               ; preds = %bb2
+  br label %L4
+
+L4:                                               ; preds = %L5, %bb2
+  %res.0 = phi i16 [ 385, %L5 ], [ 35, %entry ]     ; <i16> [#uses=1]
+  br label %L3
+
+L3:                                               ; preds = %L4, %bb2
+  %res.1 = phi i16 [ %res.0, %L4 ], [ 5, %entry ]   ; <i16> [#uses=1]
+  br label %L2
+
+L2:                                               ; preds = %L3, %bb2
+  %res.2 = phi i16 [ %res.1, %L3 ], [ 1, %entry ]   ; <i16> [#uses=1]
+  br label %L1
+
+L1:                                               ; preds = %L2, %bb2
+  %res.3 = phi i16 [ %res.2, %L2 ], [ 2, %entry ]  ; <i16> [#uses=1]
+  ret i16 %res.3
+}