PPC/s390: cppgc: Conservative stack scanning

Port 1a7f5689

R=mlippautz@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: I4db697c6a0fab9bd3c9dda4761c3af3ade509ffa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144691
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Reviewed-by: Joran Siu <joransiu@ca.ibm.com>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67093}

BUILD.gn

@@ -353,7 +353,8 @@ config("cppgc_base_config") {
   # Linux->Windows are covered as they use clang.
   if (is_clang || !is_win) {
     if (target_cpu == "x64" || target_cpu == "x86" || target_cpu == "arm" ||
-        target_cpu == "arm64") {
+        target_cpu == "arm64" || target_cpu == "ppc64" ||
+        target_cpu == "s390x") {
       defines = [ "CPPGC_SUPPORTS_CONSERVATIVE_STACK_SCAN" ]
     }
   } else if (is_win) {
@@ -3989,6 +3990,10 @@ v8_source_set("cppgc_base") {
       sources += [ "src/heap/cppgc/asm/arm/push_registers_asm.cc" ]
     } else if (target_cpu == "arm64") {
       sources += [ "src/heap/cppgc/asm/arm64/push_registers_asm.cc" ]
+    } else if (target_cpu == "ppc64") {
+      sources += [ "src/heap/cppgc/asm/ppc/push_registers_asm.cc" ]
+    } else if (target_cpu == "s390x") {
+      sources += [ "src/heap/cppgc/asm/s390/push_registers_asm.cc" ]
     }
   } else if (is_win) {
     if (target_cpu == "x64") {

src/heap/cppgc/asm/ppc/push_registers_asm.cc

+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Push all callee-saved registers to get them on the stack for conservative
+// stack scanning.
+//
+// See asm/x64/push_registers_clang.cc for why the function is not generated
+// using clang.
+
+// Do not depend on V8_TARGET_OS_* defines as some embedders may override the
+// GN toolchain (e.g. ChromeOS) and not provide them.
+
+// PPC ABI source:
+// http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html
+
+// AIX Runtime process stack:
+// https://www.ibm.com/support/knowledgecenter/ssw_aix_71/assembler/idalangref_runtime_process.html
+asm(
+#if defined(_AIX)
+    ".globl .PushAllRegistersAndIterateStack, hidden    \n"
+    ".PushAllRegistersAndIterateStack:                  \n"
+#else
+    ".globl PushAllRegistersAndIterateStack             \n"
+    ".hidden PushAllRegistersAndIterateStack            \n"
+    "PushAllRegistersAndIterateStack:                   \n"
+#endif
+    // Push all callee-saved registers.
+    // lr, TOC pointer, r16 to r31. 160 bytes.
+    // The parameter save area shall be allocated by the caller. 112 btes.
+    // At anytime, SP (r1) needs to be multiple of 16 (i.e. 16-aligned).
+    "  mflr 0                                          \n"
+    "  std 0, 16(1)                                    \n"
+#if defined(_AIX)
+    "  std 2, 40(1)                                    \n"
+#else
+    "  std 2, 24(1)                                    \n"
+#endif
+    "  stdu 1, -256(1)                                 \n"
+    "  std 14, 112(1)                                  \n"
+    "  std 15, 120(1)                                  \n"
+    "  std 16, 128(1)                                  \n"
+    "  std 17, 136(1)                                  \n"
+    "  std 18, 144(1)                                  \n"
+    "  std 19, 152(1)                                  \n"
+    "  std 20, 160(1)                                  \n"
+    "  std 21, 168(1)                                  \n"
+    "  std 22, 176(1)                                  \n"
+    "  std 23, 184(1)                                  \n"
+    "  std 24, 192(1)                                  \n"
+    "  std 25, 200(1)                                  \n"
+    "  std 26, 208(1)                                  \n"
+    "  std 27, 216(1)                                  \n"
+    "  std 28, 224(1)                                  \n"
+    "  std 29, 232(1)                                  \n"
+    "  std 30, 240(1)                                  \n"
+    "  std 31, 248(1)                                  \n"
+    // Pass 1st parameter (r3) unchanged (Stack*).
+    // Pass 2nd parameter (r4) unchanged (StackVisitor*).
+    // Save 3rd parameter (r5; IterateStackCallback).
+    "  mr 6, 5                                         \n"
+#if defined(_AIX)
+    // Set up TOC for callee.
+    "  ld 2,8(5)                                       \n"
+    // AIX uses function decorators, which means that
+    // pointers to functions do not point to code, but
+    //  instead point to metadata about them, hence
+    // need to deterrence.
+    "  ld 6,0(6)                                       \n"
+#endif
+    // Pass 3rd parameter as sp (stack pointer).
+    "  mr 5, 1                                         \n"
+#if !defined(_AIX)
+    // Set up r12 to be equal to the callee address (in order for TOC
+    // relocation). Only needed on LE Linux.
+    "  mr 12, 6                                        \n"
+#endif
+    // Call the callback.
+    "  mtctr 6                                         \n"
+    "  bctrl                                           \n"
+    // Discard all the registers.
+    "  addi 1, 1, 256                                  \n"
+    // Restore lr.
+    "  ld 0, 16(1)                                     \n"
+    "  mtlr  0                                         \n"
+#if defined(_AIX)
+    // Restore TOC pointer.
+    "  ld 2, 40(1)                                     \n"
+#else
+    "  ld 2, 24(1)                                     \n"
+#endif
+    "  blr                                             \n");

src/heap/cppgc/asm/s390/push_registers_asm.cc

+// Copyright 2020 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Push all callee-saved registers to get them on the stack for conservative
+// stack scanning.
+
+// See asm/x64/push_registers_clang.cc for why the function is not generated
+// using clang.
+
+// Do not depend on V8_TARGET_OS_* defines as some embedders may override the
+// GN toolchain (e.g. ChromeOS) and not provide them.
+
+// S390 ABI source:
+// http://refspecs.linuxbase.org/ELF/zSeries/lzsabi0_zSeries.html
+asm(".globl PushAllRegistersAndIterateStack             \n"
+    ".hidden PushAllRegistersAndIterateStack            \n"
+    "PushAllRegistersAndIterateStack:                   \n"
+    // Push all callee-saved registers.
+    // r6-r13, r14 and sp(r15)
+    "  stmg %r6, %sp, 48(%sp)                           \n"
+    // Allocate frame.
+    "  lay %sp, -160(%sp)                               \n"
+    // Pass 1st parameter (r2) unchanged (Stack*).
+    // Pass 2nd parameter (r3) unchanged (StackVisitor*).
+    // Save 3rd parameter (r4; IterateStackCallback).
+    "  lgr %r5, %r4                                     \n"
+    // Pass sp parameter as sp (stack pointer). 160+48 to point
+    // to callee saved region stored above.
+    "  lay %r4, 208(%sp)                                \n"
+    // Call the callback.
+    "  basr %r14, %r5                                   \n"
+    "  lmg %r14,%sp, 272(%sp)                           \n"
+    "  br %r14                                          \n");