8358578: Small -XX:NMethodSizeLimit triggers "not in CodeBuffer memory" assert in C1

Reviewed-by: kvn, syan, thartmann

Author: mhaessig

src/hotspot/share/c1/c1_Compilation.cpp

@@ -330,7 +330,7 @@ bool Compilation::setup_code_buffer(CodeBuffer* code, int call_stub_estimate) {
   char* locs_buffer = NEW_RESOURCE_ARRAY(char, locs_buffer_size);
   code->insts()->initialize_shared_locs((relocInfo*)locs_buffer,
                                         locs_buffer_size / sizeof(relocInfo));
-  code->initialize_consts_size(Compilation::desired_max_constant_size());
+  code->initialize_consts_size(Compilation::desired_max_constant_size);
   // Call stubs + two deopt handlers (regular and MH) + exception handler
   int stub_size = (call_stub_estimate * LIR_Assembler::call_stub_size()) +
                    LIR_Assembler::exception_handler_size() +

src/hotspot/share/c1/c1_Compilation.hpp

@@ -216,12 +216,8 @@ class Compilation: public StackObj {
   const char* bailout_msg() const                { return _bailout_msg; }
   const CompilationFailureInfo* first_failure_details() const { return _first_failure_details; }
 
-  static uint desired_max_code_buffer_size() {
-    return (uint)NMethodSizeLimit;  // default 64K
-  }
-  static uint desired_max_constant_size() {
-    return desired_max_code_buffer_size() / 10;
-  }
+  const static uint desired_max_code_buffer_size = 64*K * wordSize;
+  const static uint desired_max_constant_size = desired_max_code_buffer_size / 10;
 
   static bool setup_code_buffer(CodeBuffer* cb, int call_stub_estimate);
 

src/hotspot/share/c1/c1_Compiler.cpp

@@ -79,16 +79,15 @@ void Compiler::initialize() {
 }
 
 uint Compiler::code_buffer_size() {
-  return Compilation::desired_max_code_buffer_size() + Compilation::desired_max_constant_size();
+  return Compilation::desired_max_code_buffer_size + Compilation::desired_max_constant_size;
 }
 
 BufferBlob* Compiler::init_buffer_blob() {
   // Allocate buffer blob once at startup since allocation for each
   // compilation seems to be too expensive (at least on Intel win32).
   assert (CompilerThread::current()->get_buffer_blob() == nullptr, "Should initialize only once");
 
-  // setup CodeBuffer.  Preallocate a BufferBlob of size
-  // NMethodSizeLimit plus some extra space for constants.
+  // Setup CodeBuffer.
   BufferBlob* buffer_blob = BufferBlob::create("C1 temporary CodeBuffer", code_buffer_size());
   if (buffer_blob != nullptr) {
     CompilerThread::current()->set_buffer_blob(buffer_blob);

src/hotspot/share/c1/c1_globals.hpp

@@ -274,12 +274,6 @@
   develop(bool, InstallMethods, true,                                       \
           "Install methods at the end of successful compilations")          \
                                                                             \
-  /* The compiler assumes, in many places, that methods are at most 1MB. */ \
-  /* Therefore, we restrict this flag to at most 1MB.                    */ \
-  develop(intx, NMethodSizeLimit, (64*K)*wordSize,                          \
-          "Maximum size of a compiled method.")                             \
-          range(0, 1*M)                                                     \
-                                                                            \
   develop(intx, InstructionCountCutoff, 37000,                              \
           "If GraphBuilder adds this many instructions, bails out")         \
           range(0, max_jint)                                                \

test/hotspot/jtreg/compiler/arguments/TestC1Globals.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -21,42 +21,6 @@
  * questions.
  */
 
-/**
- * @test
- * @bug 8316653
- * @requires vm.debug
- * @summary Test flag with max value.
- *
- * @run main/othervm -XX:NMethodSizeLimit=1M
- *                   compiler.arguments.TestC1Globals
- */
-
-/**
- * @test
- * @bug 8318817
- * @requires vm.debug
- * @requires os.family == "linux"
- * @summary Test flag with max value combined with transparent huge pages on
- *          Linux.
- *
- * @run main/othervm -XX:NMethodSizeLimit=1M
- *                   -XX:+UseTransparentHugePages
- *                   compiler.arguments.TestC1Globals
- */
-
-/**
- * @test
- * @bug 8320682
- * @requires vm.debug
- * @summary Test flag with max value and specific compilation.
- *
- * @run main/othervm -XX:NMethodSizeLimit=1M
- *                   -XX:CompileOnly=java.util.HashMap::putMapEntries
- *                   -Xcomp
- *                   compiler.arguments.TestC1Globals
- *
- */
-
 /**
  * @test
  * @bug 8322781

test/hotspot/jtreg/compiler/c1/TestLinearScanOrderMain.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,6 @@
  * @bug 8207355
  * @compile TestLinearScanOrder.jasm
  * @run main/othervm -Xcomp -XX:+TieredCompilation -XX:TieredStopAtLevel=1
- *                   -XX:+IgnoreUnrecognizedVMOptions -XX:NMethodSizeLimit=655360
  *                   -XX:CompileCommand=compileonly,compiler.c1.TestLinearScanOrder::test
  *                   compiler.c1.TestLinearScanOrderMain
  */