From: Cherry Mui <cherryyz@google.com>
Date: Wed, 4 Aug 2021 22:24:47 +0000 (-0400)
Subject: compiler: make escape analysis more robust about builtin functions
X-Git-Tag: basepoints/gcc-13~5559
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac8a2fbedf59eecda6d1c049952e10946ffc4a61;p=thirdparty%2Fgcc.git

compiler: make escape analysis more robust about builtin functions

In the places where we handle builtin functions, list all
supported ones, and fail if an unexpected one is seen. So if a
new builtin function is added in the future we can detect it,
instead of silently treating it as nonescaping.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/339992
---

diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index be1a90f7aa13..394530c1cbc3 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-616ee658a6238e7de53592ebda5997f6de6a00de
+b47bcf942daa9a0c252db9b57b8f138adbfcdaa2
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/escape.cc b/gcc/go/gofrontend/escape.cc
index 347ac2534c98..c8978ac92393 100644
--- a/gcc/go/gofrontend/escape.cc
+++ b/gcc/go/gofrontend/escape.cc
@@ -1608,8 +1608,33 @@ Escape_analysis_assign::expression(Expression** pexpr)
                 }
                 break;
 
-              default:
+              case Builtin_call_expression::BUILTIN_CLOSE:
+              case Builtin_call_expression::BUILTIN_DELETE:
+              case Builtin_call_expression::BUILTIN_PRINT:
+              case Builtin_call_expression::BUILTIN_PRINTLN:
+              case Builtin_call_expression::BUILTIN_LEN:
+              case Builtin_call_expression::BUILTIN_CAP:
+              case Builtin_call_expression::BUILTIN_COMPLEX:
+              case Builtin_call_expression::BUILTIN_REAL:
+              case Builtin_call_expression::BUILTIN_IMAG:
+              case Builtin_call_expression::BUILTIN_RECOVER:
+              case Builtin_call_expression::BUILTIN_ALIGNOF:
+              case Builtin_call_expression::BUILTIN_OFFSETOF:
+              case Builtin_call_expression::BUILTIN_SIZEOF:
+                // these do not escape.
+                break;
+
+              case Builtin_call_expression::BUILTIN_ADD:
+              case Builtin_call_expression::BUILTIN_SLICE:
+                // handled in ::assign.
                 break;
+
+              case Builtin_call_expression::BUILTIN_MAKE:
+              case Builtin_call_expression::BUILTIN_NEW:
+                // should have been lowered to runtime calls at this point.
+                // fallthrough
+              default:
+                go_unreachable();
               }
             break;
           }
@@ -2372,8 +2397,35 @@ Escape_analysis_assign::assign(Node* dst, Node* src)
                     }
                     break;
 
-                  default:
+                  case Builtin_call_expression::BUILTIN_LEN:
+                  case Builtin_call_expression::BUILTIN_CAP:
+                  case Builtin_call_expression::BUILTIN_COMPLEX:
+                  case Builtin_call_expression::BUILTIN_REAL:
+                  case Builtin_call_expression::BUILTIN_IMAG:
+                  case Builtin_call_expression::BUILTIN_RECOVER:
+                  case Builtin_call_expression::BUILTIN_ALIGNOF:
+                  case Builtin_call_expression::BUILTIN_OFFSETOF:
+                  case Builtin_call_expression::BUILTIN_SIZEOF:
+                    // these do not escape.
+                    break;
+
+                  case Builtin_call_expression::BUILTIN_COPY:
+                    // handled in ::expression.
                     break;
+
+                  case Builtin_call_expression::BUILTIN_CLOSE:
+                  case Builtin_call_expression::BUILTIN_DELETE:
+                  case Builtin_call_expression::BUILTIN_PRINT:
+                  case Builtin_call_expression::BUILTIN_PRINTLN:
+                  case Builtin_call_expression::BUILTIN_PANIC:
+                    // these do not have result.
+                    // fallthrough
+                  case Builtin_call_expression::BUILTIN_MAKE:
+                  case Builtin_call_expression::BUILTIN_NEW:
+                    // should have been lowered to runtime calls at this point.
+                    // fallthrough
+                  default:
+                    go_unreachable();
                   }
                 break;
               }