From 30cc227fa79c253332ea805a3a78ddca72aea428 Mon Sep 17 00:00:00 2001
From: John Criswell <criswell@uiuc.edu>
Date: Mon, 25 Oct 2004 18:30:09 +0000
Subject: [PATCH] Modified switch generation so that only the phi values
 associated with the destination basic block are copied.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17212 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/CBackend/CBackend.cpp | 3 ++-
 lib/Target/CBackend/Writer.cpp   | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/Target/CBackend/CBackend.cpp b/lib/Target/CBackend/CBackend.cpp
index 7af9bfe4fa6..16d83c37717 100644
--- a/lib/Target/CBackend/CBackend.cpp
+++ b/lib/Target/CBackend/CBackend.cpp
@@ -1194,11 +1194,11 @@ void CWriter::visitReturnInst(ReturnInst &I) {
 }
 
 void CWriter::visitSwitchInst(SwitchInst &SI) {
-  printPHICopiesForSuccessors(SI.getParent(), 0);
 
   Out << "  switch (";
   writeOperand(SI.getOperand(0));
   Out << ") {\n  default:\n";
+  printPHICopiesForSuccessor (SI.getParent(), SI.getDefaultDest(), 2);
   printBranchToBlock(SI.getParent(), SI.getDefaultDest(), 2);
   Out << ";\n";
   for (unsigned i = 2, e = SI.getNumOperands(); i != e; i += 2) {
@@ -1206,6 +1206,7 @@ void CWriter::visitSwitchInst(SwitchInst &SI) {
     writeOperand(SI.getOperand(i));
     Out << ":\n";
     BasicBlock *Succ = cast<BasicBlock>(SI.getOperand(i+1));
+    printPHICopiesForSuccessor (SI.getParent(), Succ, 2);
     printBranchToBlock(SI.getParent(), Succ, 2);
     if (Succ == SI.getParent()->getNext())
       Out << "    break;\n";
diff --git a/lib/Target/CBackend/Writer.cpp b/lib/Target/CBackend/Writer.cpp
index 7af9bfe4fa6..16d83c37717 100644
--- a/lib/Target/CBackend/Writer.cpp
+++ b/lib/Target/CBackend/Writer.cpp
@@ -1194,11 +1194,11 @@ void CWriter::visitReturnInst(ReturnInst &I) {
 }
 
 void CWriter::visitSwitchInst(SwitchInst &SI) {
-  printPHICopiesForSuccessors(SI.getParent(), 0);
 
   Out << "  switch (";
   writeOperand(SI.getOperand(0));
   Out << ") {\n  default:\n";
+  printPHICopiesForSuccessor (SI.getParent(), SI.getDefaultDest(), 2);
   printBranchToBlock(SI.getParent(), SI.getDefaultDest(), 2);
   Out << ";\n";
   for (unsigned i = 2, e = SI.getNumOperands(); i != e; i += 2) {
@@ -1206,6 +1206,7 @@ void CWriter::visitSwitchInst(SwitchInst &SI) {
     writeOperand(SI.getOperand(i));
     Out << ":\n";
     BasicBlock *Succ = cast<BasicBlock>(SI.getOperand(i+1));
+    printPHICopiesForSuccessor (SI.getParent(), Succ, 2);
     printBranchToBlock(SI.getParent(), Succ, 2);
     if (Succ == SI.getParent()->getNext())
       Out << "    break;\n";