[COMMITTED] gccrs: backend: correctly formulate the exit condition ...

[Arthur Cohen <arthur.cohen@embecosm.com>]

From: liushuyu <liushuyu011@gmail.com>

... previously the exit condition was treated the same as the loop
condition (which is the inverse condition of the exit condition). Now
this is corrected.

gcc/rust/ChangeLog:

	* backend/rust-compile-expr.cc (CompileExpr::visit): Properly formulate
	exit condition when compiling while loops.

Signed-off-by: Zixing Liu <liushuyu011@gmail.com>

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/rust/backend/rust-compile-expr.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/gcc/rust/backend/rust-compile-expr.cc b/gcc/rust/backend/rust-compile-expr.cc
index ea146731cbe..d58e2258947 100644
--- a/gcc/rust/backend/rust-compile-expr.cc
+++ b/gcc/rust/backend/rust-compile-expr.cc
@@ -727,8 +727,11 @@ CompileExpr::visit (HIR::WhileLoopExpr &expr)
 
   tree condition
     = CompileExpr::Compile (expr.get_predicate_expr ().get (), ctx);
+  tree exit_condition
+    = fold_build1_loc (expr.get_locus ().gcc_location (), TRUTH_NOT_EXPR,
+		       boolean_type_node, condition);
   tree exit_expr
-    = ctx->get_backend ()->exit_expression (condition, expr.get_locus ());
+    = ctx->get_backend ()->exit_expression (exit_condition, expr.get_locus ());
   ctx->add_statement (exit_expr);
 
   tree code_block_stmt
-- 
2.39.1