From 08cd8d5929eac84b27788d8483fd75ab7ad13129 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Fri, 18 Sep 2020 23:21:05 +0930 Subject: [PATCH] [RS6000] Power10 libffi fixes Power10 pc-relative code doesn't use or preserve r2 as a TOC pointer. That means calling between pc-relative and TOC using code can't be done without intervening linker stubs, and a call from TOC code to pc-relative code must have a nop after the bl in order to restore r2. Now the PowerPC libffi assembly code doesn't use r2 except for the implicit use when making calls back to C, ffi_closure_helper_LINUX64 and ffi_prep_args64. So changing the assembly to interoperate with pc-relative code without stubs is easily done. * src/powerpc/linux64.S (ffi_call_LINUX64): Don't emit global entry when __PCREL__. Call using @notoc. Add nops. * src/powerpc/linux64_closure.S (ffi_closure_LINUX64): Likewise. (ffi_go_closure_linux64): Likewise. --- libffi/src/powerpc/linux64.S | 8 ++++++++ libffi/src/powerpc/linux64_closure.S | 12 +++++++++++- 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/libffi/src/powerpc/linux64.S b/libffi/src/powerpc/linux64.S index b2ae60ead6e..f0006fe90c5 100644 --- a/libffi/src/powerpc/linux64.S +++ b/libffi/src/powerpc/linux64.S @@ -36,8 +36,10 @@ .cfi_startproc # if _CALL_ELF == 2 ffi_call_LINUX64: +# ifndef __PCREL__ addis %r2, %r12, .TOC.-ffi_call_LINUX64@ha addi %r2, %r2, .TOC.-ffi_call_LINUX64@l +# endif .localentry ffi_call_LINUX64, . - ffi_call_LINUX64 # else .section ".opd","aw" @@ -89,9 +91,15 @@ ffi_call_LINUX64: /* Call ffi_prep_args64. */ mr %r4, %r1 # if defined _CALL_LINUX || _CALL_ELF == 2 +# ifdef __PCREL__ + bl ffi_prep_args64@notoc +# else bl ffi_prep_args64 + nop +# endif # else bl .ffi_prep_args64 + nop # endif # if _CALL_ELF == 2 diff --git a/libffi/src/powerpc/linux64_closure.S b/libffi/src/powerpc/linux64_closure.S index 6487d2a2970..3e30db36190 100644 --- a/libffi/src/powerpc/linux64_closure.S +++ b/libffi/src/powerpc/linux64_closure.S @@ -37,8 +37,10 @@ .cfi_startproc # if _CALL_ELF == 2 ffi_closure_LINUX64: +# ifndef __PCREL__ addis %r2, %r12, .TOC.-ffi_closure_LINUX64@ha addi %r2, %r2, .TOC.-ffi_closure_LINUX64@l +# endif .localentry ffi_closure_LINUX64, . - ffi_closure_LINUX64 # else .section ".opd","aw" @@ -143,7 +145,7 @@ ffi_closure_LINUX64: stfd %f12, -104+(11*8)(%r1) stfd %f13, -104+(12*8)(%r1) - # load up the pointer to the saved fpr registers */ + # load up the pointer to the saved fpr registers addi %r8, %r1, -104 # load up the pointer to the result storage @@ -155,9 +157,15 @@ ffi_closure_LINUX64: # make the call # if defined _CALL_LINUX || _CALL_ELF == 2 +# ifdef __PCREL__ + bl ffi_closure_helper_LINUX64@notoc +# else bl ffi_closure_helper_LINUX64 + nop +# endif # else bl .ffi_closure_helper_LINUX64 + nop # endif .Lret: @@ -396,8 +404,10 @@ ffi_closure_LINUX64: .cfi_startproc # if _CALL_ELF == 2 ffi_go_closure_linux64: +# ifndef __PCREL__ addis %r2, %r12, .TOC.-ffi_go_closure_linux64@ha addi %r2, %r2, .TOC.-ffi_go_closure_linux64@l +# endif .localentry ffi_go_closure_linux64, . - ffi_go_closure_linux64 # else .section ".opd","aw" -- 2.30.2