https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124798
--- Comment #6 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by H.J. Lu <[email protected]>: https://gcc.gnu.org/g:94082ac189cf318ea4ad52ffdf9fa5f941ebcf9e commit r17-2209-g94082ac189cf318ea4ad52ffdf9fa5f941ebcf9e Author: H.J. Lu <[email protected]> Date: Tue Apr 14 18:37:20 2026 +0800 x86: Implement TARGET_FNTYPE_ABI Implement TARGET_FNTYPE_ABI to avoid spills of callee-saved registers when calling functions with no_caller_saved_registers attribute. After commit 754c6600fe058f1026098fde57860bbc38cc28fe Author: Richard Sandiford <[email protected]> Date: Wed Jun 3 13:11:17 2026 +0100 Add CALL_INSN_ABI_ID there is no need for ix86_expand_call to add clobbers for when one ABI calls another ABI. ABI_ALTERNATE is the alternate function ABI from the system ABI. If ix86_abi is SYSV_ABI, ABI_ALTERNATE is the function ABI for MS_ABI. Otherwise, ABI_ALTERNATE is the function ABI for SYSV_ABI. This target hook also properly marks the implicit __tls_get_addr call: (call_insn/u 9 8 10 (parallel [ (set (reg:DI 0 ax) (call:DI (mem:QI (symbol_ref:DI ("__tls_get_addr")) [0 S1 A8]) (const_int 0 [0]))) (unspec:DI [ (reg/f:DI 7 sp) ] UNSPEC_TLS_LD_BASE) (clobber (reg:DI 5 di)) ]) "x.c":7:16 -1 (expr_list:REG_EH_REGION (const_int -2147483648 [0xffffffff80000000]) (nil)) (nil) 0) with ABI_DEFAULT function ABI. Tested on Linux/x86-64 and with CPython 3.14.4. gcc/ PR target/124798 PR target/125436 * config/i386/i386-expand.cc: Include "function-abi.h". (x86_64_ms_sysv_extra_clobbered_registers): Removed. (ix86_expand_call): Don't add explicit call and ABI-switch clobbers. * config/i386/i386-features.cc (ix86_emit_tls_call): Call ix86_tls_get_addr_abi to get GNU TLS ABI and use it, instead of default_function_abi, for registers clobbered by GNU TLS call. (ix86_place_single_tls_call): Set CALL_INSN_ABI_ID on TLS calls. * config/i386/i386-options.cc (ix86_set_current_function): Don't call reinit_regs. * config/i386/i386-protos.h (ix86_type_no_callee_saved_registers_p): Removed. (ix86_tls_get_addr_abi): New. * config/i386/i386.cc (ix86_alternate_abi): New prototype. (ix86_conditional_register_usage): Changed to describe the system ABI. (ix86_type_no_callee_saved_registers_p): Make it static. (ix86_function_value_regno_p): Replace ix86_cfun_abi () with ix86_abi. (ix86_save_reg): Only check TYPE_NO_CALLEE_SAVED_REGISTERS as a special case. (ix86_tls_get_addr_abi): New. (legitimize_tls_address): Set CALL_INSN_ABI_ID on TLS calls. Call ix86_alternate_abi to initialize the alternate function ABI. (ix86_initialize_abi): New function. (ix86_no_callee_saved_abi): Likewise. (ix86_no_caller_saved_abi): Likewise. (ix86_standard_abi): Likewise. (ix86_alternate_abi): Likewise. (ix86_function_abi_id): Likewise. (ix86_fntype_abi): Likewise. (ix86_hard_regno_call_part_clobbered): Handle newly added ABIs. (TARGET_FNTYPE_ABI): New. * config/i386/i386.md: Add ABI_ALTERNATE, ABI_NO_CALLEE_SAVED, ABI_NO_CALLER_SAVED_RETURN_VOID, ABI_NO_CALLER_SAVED_RETURN_AX, ABI_NO_CALLER_SAVED_RETURN_AX_DX, ABI_NO_CALLER_SAVED_RETURN_AX_XMM0, ABI_NO_CALLER_SAVED_RETURN_XMM0 and ABI_NO_CALLER_SAVED_RETURN_XMM0_XMM1. gcc/testsuite/ PR target/124798 PR target/125436 * gcc.target/i386/abi-mix-1.c: New test. * gcc.target/i386/abi-mix-2.c: Likewise. * gcc.target/i386/no-callee-saved-20.c: Likewise. * gcc.target/i386/no-caller-saved-1-ms.c: Likewise. * gcc.target/i386/no-caller-saved-1-sysv.c: Likewise. * gcc.target/i386/no-caller-saved-1.c: Likewise. * gcc.target/i386/no-caller-saved-2.c: Likewise. * gcc.target/i386/no-caller-saved-3.c: Likewise. * gcc.target/i386/no-caller-saved-4.c: Likewise. * gcc.target/i386/no-caller-saved-5.c: Likewise. * gcc.target/i386/no-caller-saved-6.c: Likewise. * gcc.target/i386/no-caller-saved-7.c: Likewise. * gcc.target/i386/no-caller-saved-8.c: Likewise. * gcc.target/i386/no-caller-saved-9.c: Likewise. * gcc.target/i386/no-caller-saved-10.c: Likewise. * gcc.target/i386/no-caller-saved-11.c: Likewise. * gcc.target/i386/pr125436-1a.c: Likewise. * gcc.target/i386/pr125436-1b.c: Likewise. * gcc.target/i386/pr125436-2a.c: Likewise. * gcc.target/i386/pr125436-2b.c: Likewise. * gcc.target/i386/pr125436-3.c: Likewise. * gcc.target/i386/pr125436-4.c: Likewise. * gcc.target/i386/pr119784b.c: Adjusted for unused RBP. * gcc.target/i386/no-callee-saved-18.c: Don't check frame register. * gcc.target/i386/no-callee-saved-19b.c: Update the expected instruction order. * gcc.target/i386/no-callee-saved-19d.c: Likewise. * gcc.target/i386/no-callee-saved-19e.c: Likewise. * gcc.target/i386/no-callee-saved-2.c: Check frame register isn't saved nor restored in 64-bit mode. * gcc.target/i386/no-callee-saved-8.c: Expect no saving nor restoring caller-saved registers. * gcc.target/i386/no-callee-saved-9.c: Likewise. * gcc.target/i386/preserve-none-14.c: Don't check frame register. * gcc.target/i386/preserve-none-23.c: Likewise. * gcc.target/i386/preserve-none-7.c: Check frame register isn't saved nor restored in 64-bit mode. Signed-off-by: H.J. Lu <[email protected]> Co-Authored-by: Richard Sandiford <[email protected]> Signed-off-by: H.J. Lu <[email protected]>
