Enable AMD znver4 support and add instruction reservations

2022-09-28  Tejas Joshi <TejasSanjay.Joshi@amd.com>

gcc/ChangeLog:

	* common/config/i386/cpuinfo.h (get_amd_cpu): Recognize znver4.
	* common/config/i386/i386-common.cc (processor_names): Add znver4.
	(processor_alias_table): Add znver4 and modularize old znvers.
	* common/config/i386/i386-cpuinfo.h (processor_subtypes):
	AMDFAM19H_ZNVER4.
	* config.gcc (x86_64-*-* |...): Likewise.
	* config/i386/driver-i386.cc (host_detect_local_cpu): Let
	-march=native recognize znver4 cpus.
	* config/i386/i386-c.cc (ix86_target_macros_internal): Add znver4.
	* config/i386/i386-options.cc (m_ZNVER4): New definition.
	(m_ZNVER): Include m_ZNVER4.
	(processor_cost_table): Add znver4.
	* config/i386/i386.cc (ix86_reassociation_width): Likewise.
	* config/i386/i386.h (processor_type): Add PROCESSOR_ZNVER4.
	(PTA_ZNVER1): New definition.
	(PTA_ZNVER2): Likewise.
	(PTA_ZNVER3): Likewise.
	(PTA_ZNVER4): Likewise.
	* config/i386/i386.md (define_attr "cpu"): Add znver4 and rename
	md file.
	* config/i386/x86-tune-costs.h (znver4_cost): New definition.
	* config/i386/x86-tune-sched.cc (ix86_issue_rate): Add znver4.
	(ix86_adjust_cost): Likewise.
	* config/i386/znver1.md: Rename to znver.md.
	* config/i386/znver.md: Add new reservations for znver4.
	* doc/extend.texi: Add details about znver4.
	* doc/invoke.texi: Likewise.

gcc/testsuite/ChangeLog:

	* gcc.target/i386/funcspec-56.inc: Handle new march.
	* g++.target/i386/mv29.C: Likewise.