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* tcg: Fix prototypes for tcg_out_vec_op and tcg_out_opMiroslav Rezanina2021-03-171-8/+11
| | | | | | | | | | | | | | | | | There are two different versions of prototype for tcg_out_op and tcg_out_vec_op functions: 1) using const TCGArg *args and const int *const_args arguments 2) using const TCGArg args[TCG_MAX_OP_ARGS] and const int const_args[TCG_MAX_OP_ARGS] aguments. This duality causes warnings on GCC 11 and prevents build using --enable-werror. As second version provides more information, unify functions prototypes to this variant. Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com> Message-Id: <20210312121418.139093-1-mrezanin@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Manage splitwx in tc_ptr_to_region_tree by handRichard Henderson2021-03-061-2/+18
| | | | | | | | | The use in tcg_tb_lookup is given a random pc that comes from the pc of a signal handler. Do not assert that the pointer is already within the code gen buffer at all, much less the writable mirror of it. Fixes: db0c51a3803 Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Split out tcg_raise_tb_overflowRichard Henderson2021-03-061-2/+7
| | | | | | | Allow other places in tcg to restart with a smaller tb. Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Remove TCG_TARGET_CON_SET_HRichard Henderson2021-02-021-12/+0Star
| | | | | | | | | All backends have now been converted to tcg-target-con-set.h, so we can remove the fallback code. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg/i386: Split out constraint sets to tcg-target-con-set.hRichard Henderson2021-02-021-0/+119
| | | | | | | | This exports the constraint sets from tcg_target_op_def to a place we will be able to manipulate more in future. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Remove TCG_TARGET_CON_STR_HRichard Henderson2021-02-021-16/+0Star
| | | | | | | | | All backends have now been converted to tcg-target-con-str.h, so we can remove the fallback code. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg/i386: Split out target constraints to tcg-target-con-str.hRichard Henderson2021-02-021-5/+28
| | | | | | | | | | This eliminates the target-specific function target_parse_constraint and folds it into the single caller, process_op_defs. Since this is done directly into the switch statement, duplicates are compilation errors rather than silently ignored at runtime. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Restart code generation when we run out of tempsRichard Henderson2021-01-241-3/+8
| | | | | | | | | | | | Some large translation blocks can generate so many unique constants that we run out of temps to hold them. In this case, longjmp back to the start of code generation and restart with a smaller translation block. Buglink: https://bugs.launchpad.net/bugs/1912065 Tested-by: BALATON Zoltan <balaton@eik.bme.hu> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Toggle page execution for Apple SiliconRoman Bolshakov2021-01-231-0/+1
| | | | | | | | | | | | | | | Pages can't be both write and executable at the same time on Apple Silicon. macOS provides public API to switch write protection [1] for JIT applications, like TCG. 1. https://developer.apple.com/documentation/apple_silicon/porting_just-in-time_compilers_to_apple_silicon Tested-by: Alexander Graf <agraf@csgraf.de> Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com> Message-Id: <20210113032806.18220-1-r.bolshakov@yadro.com> [rth: Inline the qemu_thread_jit_* functions; drop the MAP_JIT change for a follow-on patch.] Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Add tcg_reg_alloc_dup2Richard Henderson2021-01-131-0/+97
| | | | | | | There are several ways we can expand a vector dup of a 64-bit element on a 32-bit host. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Remove movi and dupi opcodesRichard Henderson2021-01-131-17/+1Star
| | | | | | | | | These are now completely covered by mov from a TYPE_CONST temporary. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Use tcg_constant_{i32,i64,vec} with gvec expandersRichard Henderson2021-01-131-0/+8
| | | | Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Convert tcg_gen_dupi_vec to TCG_CONSTRichard Henderson2021-01-131-6/+1Star
| | | | | | | | Because we now store uint64_t in TCGTemp, we can now always store the full 64-bit duplicate immediate. So remove the difference between 32- and 64-bit hosts. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Introduce TYPE_CONST temporariesRichard Henderson2021-01-131-47/+177
| | | | | | | | | These will hold a single constant for the duration of the TB. They are hashed, so that each value has one temp across the TB. Not used yet, this is all infrastructure. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Expand TCGTemp.val to 64-bitsRichard Henderson2021-01-131-1/+1
| | | | | | | This will reduce the differences between 32-bit and 64-bit hosts, allowing full 64-bit constants to be created with the same interface. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Add temp_readonlyRichard Henderson2021-01-131-11/+10Star
| | | | | | | | | In most, but not all, places that we check for TEMP_FIXED, we are really testing that we do not modify the temporary. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Consolidate 3 bits into enum TCGTempKindRichard Henderson2021-01-131-50/+76
| | | | | | | | | The temp_fixed, temp_global, temp_local bits are all related. Combine them into a single enumeration. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Increase tcg_out_dupi_vec immediate to int64_tRichard Henderson2021-01-131-5/+26
| | | | | | | | | | | | While we don't store more than tcg_target_long in TCGTemp, we shouldn't be limited to that for code generation. We will be able to use this for INDEX_op_dup2_vec with 2 constants. Also pass along the minimal vece that may be said to apply to the constant. This allows some simplification in the various backends. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Use tcg_out_dupi_vec from temp_loadRichard Henderson2021-01-131-1/+5
| | | | | | | Having dupi pass though movi is confusing and arguably wrong. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Constify tcg_code_gen_epilogueRichard Henderson2021-01-071-1/+1
| | | | | | | | | Now that all native tcg hosts support splitwx, make this pointer const. Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Adjust tcg_register_jit for constRichard Henderson2021-01-071-5/+5
| | | | | | | | We must change all targets at once, since all must match the declaration in tcg.c. Reviewed-by: Joelle van Dyne <j@getutm.app> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Adjust tcg_out_label for constRichard Henderson2021-01-071-3/+3
| | | | | | | | | | Simplify the arguments to always use s->code_ptr instead of take it as an argument. That makes it easy to ensure that the value_ptr is always the rx version. Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Adjust tcg_out_call for constRichard Henderson2021-01-071-1/+1
| | | | | | | | | We must change all targets at once, since all must match the declaration in tcg.c. Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Adjust TCGLabel for constRichard Henderson2021-01-071-1/+1
| | | | | | | | | Change TCGLabel.u.value_ptr to const, and initialize it with tcg_splitwx_to_rx. Propagate const through tcg/host/ only as far as needed to avoid errors from the value_ptr change. Reviewed-by: Joelle van Dyne <j@getutm.app> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Introduce tcg_splitwx_to_{rx,rw}Richard Henderson2021-01-071-6/+50
| | | | | | | | | | | Add two helper functions, using a global variable to hold the displacement. The displacement is currently always 0, so no change in behaviour. Begin using the functions in tcg common code only. Reviewed-by: Joelle van Dyne <j@getutm.app> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Move tcg epilogue pointer out of TCGContextRichard Henderson2021-01-071-1/+2
| | | | | | | | This value is constant across all thread-local copies of TCGContext, so we might as well move it out of thread-local storage. Reviewed-by: Joelle van Dyne <j@getutm.app> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Move tcg prologue pointer out of TCGContextRichard Henderson2021-01-071-1/+8
| | | | | | | | | | | | | | | | | This value is constant across all thread-local copies of TCGContext, so we might as well move it out of thread-local storage. Use the correct function pointer type, and name the variable tcg_qemu_tb_exec, which means that we are able to remove the macro that does the casting. Replace HAVE_TCG_QEMU_TB_EXEC with CONFIG_TCG_INTERPRETER, as this is somewhat clearer in intent. Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* util: Enhance flush_icache_range with separate data pointerRichard Henderson2021-01-071-2/+4
| | | | | | | | | | | | | We are shortly going to have a split rw/rx jit buffer. Depending on the host, we need to flush the dcache at the rw data pointer and flush the icache at the rx code pointer. For now, the two passed pointers are identical, so there is no effective change in behaviour. Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Do not flush icache for interpreterRichard Henderson2021-01-071-0/+4
| | | | | | | | This is currently a no-op within tci/tcg-target.h, but is about to be moved to a more generic location. Reviewed-by: Joelle van Dyne <j@getutm.app> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Introduce INDEX_op_qemu_st8_i32Richard Henderson2021-01-071-0/+4
| | | | | | | | | Enable this on i386 to restrict the set of input registers for an 8-bit store, as required by the architecture. This removes the last use of scratch registers for user-only mode. Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* util: Extract flush_icache_range to cacheflush.cRichard Henderson2021-01-021-0/+1
| | | | | | | | | | | | This has been a tcg-specific function, but is also in use by hardware accelerators via physmem.c. This can cause link errors when tcg is disabled. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Joelle van Dyne <j@getutm.app> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-Id: <20201214140314.18544-3-richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* tcg: Remove assert from set_jmp_reset_offsetRichard Henderson2020-11-041-4/+5
| | | | | | | | | | | | Since 6e6c4efed99, there has been a more appropriate range check done later at the end of tcg_gen_code. There, a failing range check results in a returned error code, which causes the TB to be restarted at half the size. Reported-by: Sai Pavan Boddu <saipava@xilinx.com> Tested-by: Sai Pavan Boddu <sai.pavan.boddu@xilinx.com> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Do not kill globals at conditional branchesRichard Henderson2020-10-271-2/+53
| | | | | | | | | | | | | We can easily register allocate the entire extended basic block (in this case, the set of blocks connected by fallthru), simply by not discarding the register state at the branch. This does not help blocks starting with a label, as they are reached via a taken branch, and that would require saving the complete register state at the branch. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Move some TCG_CT_* bits to TCGArgConstraint bitfieldsRichard Henderson2020-10-081-16/+12Star
| | | | | | | | | | | | These are easier to set and test when they have their own fields. Reduce the size of alias_index and sort_index to 4 bits, which is sufficient for TCG_MAX_OP_ARGS. This leaves only the bits indicating constants within the ct field. Move all initialization to allocation time, rather than init individual fields in process_op_defs. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Remove TCG_CT_REGRichard Henderson2020-10-081-11/+4Star
| | | | | | | | This wasn't actually used for anything, really. All variable operands must accept registers, and which are indicated by the set in TCGArgConstraint.regs. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Move sorted_args into TCGArgConstraint.sort_indexRichard Henderson2020-10-081-18/+17Star
| | | | | | | This uses an existing hole in the TCGArgConstraint structure and will be convenient for keeping the data in one place. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Drop union from TCGArgConstraintRichard Henderson2020-10-081-11/+11
| | | | | | | | The union is unused; let "regs" appear in the main structure without the "u.regs" wrapping. Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* disas: Move host asm annotations to tb_gen_codeRichard Henderson2020-10-031-2/+2
| | | | | | | | | | | | Instead of creating GStrings and passing them into log_disas, just print the annotations directly in tb_gen_code. Fix the annotations for the slow paths of the TB, after the part implementing the final guest instruction. Reviewed-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* qemu/atomic.h: rename atomic_ to qatomic_Stefan Hajnoczi2020-09-231-29/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | clang's C11 atomic_fetch_*() functions only take a C11 atomic type pointer argument. QEMU uses direct types (int, etc) and this causes a compiler error when a QEMU code calls these functions in a source file that also included <stdatomic.h> via a system header file: $ CC=clang CXX=clang++ ./configure ... && make ../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid) Avoid using atomic_*() names in QEMU's atomic.h since that namespace is used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h and <stdatomic.h> can co-exist. I checked /usr/include on my machine and searched GitHub for existing "qatomic_" users but there seem to be none. This patch was generated using: $ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \ sort -u >/tmp/changed_identifiers $ for identifier in $(</tmp/changed_identifiers); do sed -i "s%\<$identifier\>%q$identifier%g" \ $(git grep -I -l "\<$identifier\>") done I manually fixed line-wrap issues and misaligned rST tables. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
* meson: rename included C source files to .c.incPaolo Bonzini2020-08-211-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | With Makefiles that have automatically generated dependencies, you generated includes are set as dependencies of the Makefile, so that they are built before everything else and they are available when first building the .c files. Alternatively you can use a fine-grained dependency, e.g. target/arm/translate.o: target/arm/decode-neon-shared.inc.c With Meson you have only one choice and it is a third option, namely "build at the beginning of the corresponding target"; the way you express it is to list the includes in the sources of that target. The problem is that Meson decides if something is a source vs. a generated include by looking at the extension: '.c', '.cc', '.m', '.C' are sources, while everything else is considered an include---including '.inc.c'. Use '.c.inc' to avoid this, as it is consistent with our other convention of using '.rst.inc' for included reStructuredText files. The editorconfig file is adjusted. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* tcg: call qemu_spin_destroy for tb->jmp_lockEmilio G. Cota2020-06-161-0/+9
| | | | | | | | | Signed-off-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Robert Foley <robert.foley@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> [RF: minor changes + remove tb_destroy_func] Message-Id: <20200609200738.445-7-robert.foley@linaro.org> Message-Id: <20200612190237.30436-10-alex.bennee@linaro.org>
* tcg: Improve move ops in liveness_pass_2Richard Henderson2020-06-021-22/+56
| | | | | | | | If the output of the move is dead, then the last use is in the store. If we propagate the input to the store, then we can remove the move opcode entirely. Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Implement gvec support for rotate by scalarRichard Henderson2020-06-021-0/+2
| | | | | | | | | | No host backend support yet, but the interfaces for rotls are in place. Only implement left-rotate for now, as the only known use of vector rotate by scalar is s390x, so any right-rotate would be unused and untestable. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* tcg: Implement gvec support for rotate by vectorRichard Henderson2020-06-021-0/+3
| | | | | | | | | | | No host backend support yet, but the interfaces for rotlv and rotrv are in place. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- v3: Drop the generic expansion from rot to shift; we can do better for each backend, and then this code becomes unused.
* tcg: Implement gvec support for rotate by immediateRichard Henderson2020-06-021-0/+2
| | | | | | | | | | No host backend support yet, but the interfaces for rotli are in place. Canonicalize immediate rotate to the left, based on a survey of architectures, but provide both left and right shift interfaces to the translators. Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* disas: include an optional note for the start of disassemblyAlex Bennée2020-05-151-2/+2
| | | | | | | | | | | This will become useful shortly for providing more information about output assembly inline. While there fix up the indenting and code formatting in disas(). Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20200513175134.19619-9-alex.bennee@linaro.org>
* tcg: Search includes from the project root source directoryPhilippe Mathieu-Daudé2020-01-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently search both the root and the tcg/ directories for tcg files: $ git grep '#include "tcg/' | wc -l 28 $ git grep '#include "tcg[^/]' | wc -l 94 To simplify the preprocessor search path, unify by expliciting the tcg/ directory. Patch created mechanically by running: $ for x in \ tcg.h tcg-mo.h tcg-op.h tcg-opc.h \ tcg-op-gvec.h tcg-gvec-desc.h; do \ sed -i "s,#include \"$x\",#include \"tcg/$x\"," \ $(git grep -l "#include \"$x\""); \ done Acked-by: David Gibson <david@gibson.dropbear.id.au> (ppc parts) Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Reviewed-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Message-Id: <20200101112303.20724-2-philmd@redhat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* Add use of RCU for qemu_logfile.Robert Foley2019-12-181-2/+10
| | | | | | | | | | | | | | | | | | | | | This now allows changing the logfile while logging is active, and also solves the issue of a seg fault while changing the logfile. Any read access to the qemu_logfile handle will use the rcu_read_lock()/unlock() around the use of the handle. To fetch the handle we will use atomic_rcu_read(). We also in many cases do a check for validity of the logfile handle before using it to deal with the case where the file is closed and set to NULL. The cases where we write to the qemu_logfile will use atomic_rcu_set(). Writers will also use call_rcu() with a newly added qemu_logfile_free function for freeing/closing when readers have finished. Signed-off-by: Robert Foley <robert.foley@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20191118211528.3221-6-robert.foley@linaro.org>
* qemu_log_lock/unlock now preserves the qemu_logfile handle.Robert Foley2019-12-181-8/+8
| | | | | | | | | | | | | | | | qemu_log_lock() now returns a handle and qemu_log_unlock() receives a handle to unlock. This allows for changing the handle during logging and ensures the lock() and unlock() are for the same file. Also in target/tilegx/translate.c removed the qemu_log_lock()/unlock() calls (and the log("\n")), since the translator can longjmp out of the loop if it attempts to translate an instruction in an inaccessible page. Signed-off-by: Robert Foley <robert.foley@linaro.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20191118211528.3221-5-robert.foley@linaro.org>
* plugin-gen: add module for TCG-related codeEmilio G. Cota2019-10-281-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>