analyzer: warn on invalid shift counts [PR97424]

analyzer: warn on invalid shift counts [PR97424]

This patch implements -Wanalyzer-shift-count-negative
and -Wanalyzer-shift-count-overflow, analogous to the C/C++
warnings -Wshift-count-negative and -Wshift-count-overflow, but
implemented via interprocedural path analysis rather than via parsing
in a front end, and thus capable of detecting interprocedural cases that the
warnings implemented in the front ends can miss.

gcc/analyzer/ChangeLog:
	PR tree-optimization/97424
	* analyzer.opt (Wanalyzer-shift-count-negative): New.
	(Wanalyzer-shift-count-overflow): New.
	* region-model.cc (class shift_count_negative_diagnostic): New.
	(class shift_count_overflow_diagnostic): New.
	(region_model::get_gassign_result): Complain about shift counts that
	are negative or are >= the operand's type's width.

gcc/ChangeLog:
	PR tree-optimization/97424
	* doc/invoke.texi (Static Analyzer Options): Add
	-Wno-analyzer-shift-count-negative and
	-Wno-analyzer-shift-count-overflow.
	(-Wno-analyzer-shift-count-negative): New.
	(-Wno-analyzer-shift-count-overflow): New.

gcc/testsuite/ChangeLog:
	PR tree-optimization/97424
	* gcc.dg/analyzer/invalid-shift-1.c: New test.