replace switch stmt with an assert, generate li 0 instead of lis 0 for 0,

to make the code follow people's expectations better.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22861 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/PPCISelPattern.cpp b/lib/Target/PowerPC/PPCISelPattern.cpp
index 2f09a63959332ec04edf081b0a79a2850108cf7c..6eddcc48f1ea0b59c4b7cac71279923e624e2b73 100644 (file)
--- a/lib/Target/PowerPC/PPCISelPattern.cpp
+++ b/lib/Target/PowerPC/PPCISelPattern.cpp
@@ -1732,26 +1732,23 @@ unsigned ISel::SelectExpr(SDOperand N, bool Recording) {
     return Result;
   }
 
-  case ISD::Constant:
-    switch (N.getValueType()) {
-    default: assert(0 && "Cannot use constants of this type!");
-    case MVT::i32:
-      {
-        int v = (int)cast<ConstantSDNode>(N)->getSignExtended();
-        unsigned Hi = Hi16(v);
-        unsigned Lo = Lo16(v);
-        if (Hi && Lo) {
-          Tmp1 = MakeIntReg();
-          BuildMI(BB, PPC::LIS, 1, Tmp1).addSImm(Hi);
-          BuildMI(BB, PPC::ORI, 2, Result).addReg(Tmp1).addImm(Lo);
-        } else if (Lo) {
-          BuildMI(BB, PPC::LI, 1, Result).addSImm(Lo);
-        } else {
-          BuildMI(BB, PPC::LIS, 1, Result).addSImm(Hi);
-        }
-      }
+  case ISD::Constant: {
+    assert(N.getValueType() == MVT::i32 &&
+           "Only i32 constants are legal on this target!");
+    int v = (int)cast<ConstantSDNode>(N)->getValue();
+    unsigned Hi = Hi16(v);
+    unsigned Lo = Lo16(v);
+    if (Hi && Lo) {
+      Tmp1 = MakeIntReg();
+      BuildMI(BB, PPC::LIS, 1, Tmp1).addSImm(Hi);
+      BuildMI(BB, PPC::ORI, 2, Result).addReg(Tmp1).addImm(Lo);
+    } else if (Hi) {
+      BuildMI(BB, PPC::LIS, 1, Result).addSImm(Hi);
+    } else {
+      BuildMI(BB, PPC::LI, 1, Result).addSImm(Lo);
     }
     return Result;
+  }
 
   case ISD::ConstantFP: {
     ConstantFPSDNode *CN = cast<ConstantFPSDNode>(N);