[cfe-commits] r45779 - /cfe/trunk/AST/Expr.cpp

[Chris Lattner]

Author: lattner
Date: Wed Jan  9 12:59:34 2008
New Revision: 45779

URL: http://llvm.org/viewvc/llvm-project?rev=45779&view=rev
Log:
Fix isIntegerConstantExpr to compare against zero for casts to bool instead of
truncating.  This allows us to compile:
 void foo() {
  static _Bool foo = 4;
}

into:
@foo1 = internal global i8 1
instead of:
@foo1 = internal global i8 4

Modified:
    cfe/trunk/AST/Expr.cpp

Modified: cfe/trunk/AST/Expr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/AST/Expr.cpp?rev=45779&r1=45778&r2=45779&view=diff

==============================================================================
--- cfe/trunk/AST/Expr.cpp (original)
+++ cfe/trunk/AST/Expr.cpp Wed Jan  9 12:59:34 2008
@@ -846,7 +846,11 @@
       
       // Figure out if this is a truncate, extend or noop cast.
       // If the input is signed, do a sign extend, noop, or truncate.
-      if (SubExpr->getType()->isSignedIntegerType())
+      if (getType()->isBooleanType()) {
+        // Conversion to bool compares against zero.
+        Result = Result != 0;
+        Result.zextOrTrunc(DestWidth);
+      } else if (SubExpr->getType()->isSignedIntegerType())
         Result.sextOrTrunc(DestWidth);
       else  // If the input is unsigned, do a zero extend, noop, or truncate.
         Result.zextOrTrunc(DestWidth);
@@ -865,6 +869,13 @@
       if (Loc) *Loc = Operand->getLocStart();
       return false;
     }
+
+    // If the destination is boolean, compare against zero.
+    if (getType()->isBooleanType()) {
+      Result = !FL->getValue().isZero();
+      Result.zextOrTrunc(DestWidth);
+      break;
+    }     
     
     // Determine whether we are converting to unsigned or signed.
     bool DestSigned = getType()->isSignedIntegerType();