Commit graph

4206 commits

Author SHA1 Message Date
Peter Maydell 3a5701e030
target/arm: Use ARMMMUFaultInfo in deliver_fault()
Now that ARMMMUFaultInfo is guaranteed to have enough information
to construct a fault status code, we can pass it in to the
deliver_fault() function and let it generate the correct type
of FSR for the destination, rather than relying on the value
provided by get_phys_addr().

I don't think there are any cases the old code was getting
wrong, but this is more obviously correct.

Backports commit 681f9a89d201d7891e2c60dff5e5415d8f618518 from qemu
2018-03-05 13:59:50 -05:00
Peter Maydell 4d666dbb99
target/arm: Convert get_phys_addr_pmsav8() to not return FSC values
Make get_phys_addr_pmsav8() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit 3f551b5b7380ff131fe22944aa6f5b166aa13caf from qemu
2018-03-05 13:57:33 -05:00
Peter Maydell 3eb4a2ea84
target/arm: Convert get_phys_addr_pmsav7() to not return FSC values
Make get_phys_addr_pmsav7() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit 9375ad15338b24e06109071ac3a85df48a2cc2e6 from qemu
2018-03-05 13:55:20 -05:00
Peter Maydell 79b2c4b1e7
target/arm: Convert get_phys_addr_pmsav5() to not return FSC values
Make get_phys_addr_pmsav5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Note that PMSAv5 does not define any guest-visible fault status
register, so the different "fsr" values we were previously
returning are entirely arbitrary. So we can just switch to using
the most appropriae fi->type values without worrying that we
need to special-case FaultInfo->FSC conversion for PMSAv5.

Backports commit 53a4e5c5b07b2f50c538511b74b0d3d4964695ea from qemu
2018-03-05 13:54:05 -05:00
Peter Maydell 013e7873ee
target/arm: Convert get_phys_addr_lpae() to not return FSC values
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit da909b2c23a68e57bbcb6be98229e40df606f0c8 from qemu
2018-03-05 13:52:18 -05:00
Peter Maydell c6496ec00a
target/arm: Convert get_phys_addr_v6() to not return FSC values
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit f06cf243945ccb24cb9578304306ae7fcb4cf3fd from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 4ccf3c3927
target/arm: Convert get_phys_addr_v5() to not return FSC values
Make get_phys_addr_v5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit f989983e8dc9be6bc3468c6dbe46fcb1501a740c from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 457e4f35ac
target/arm: Remove fsr argument from arm_ld*_ptw()
All the callers of arm_ldq_ptw() and arm_ldl_ptw() ignore the value
that those functions store in the fsr argument on failure: if they
return failure to their callers they will always overwrite the fsr
value with something else.

Remove the argument from these functions and S1_ptw_translate().
This will simplify removing fsr from the calling functions.

Backports commit 3795a6de9f7ec4a7e3dcb8bf02a88a014147b0b0 from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 211cbde764
target/arm: Provide fault type enum and FSR conversion functions
Currently get_phys_addr() and its various subfunctions return
a hard-coded fault status register value for translation
failures. This is awkward because FSR values these days may
be either long-descriptor format or short-descriptor format.
Worse, the right FSR type to use doesn't depend only on the
translation table being walked -- some cases, like fault
info reported to AArch32 EL2 for some kinds of ATS operation,
must be in long-descriptor format even if the translation
table being walked was short format. We can't get those cases
right with our current approach.

Provide fields in the ARMMMUFaultInfo struct which allow
get_phys_addr() to provide sufficient information for a caller to
construct an FSR value themselves, and utility functions which do
this for both long and short format FSR values, as a first step in
switching get_phys_addr() and its children to only returning the
failure cause in the ARMMMUFaultInfo struct.

Backports commit 1fa498fe0de979030bd1f481046e9f1c5574a584 from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 8fe6b6c308
target/arm: Implement TT instruction
Implement the TT instruction which queries the security
state and access permissions of a memory location.

Backports commit 5158de241b0fb344a6c948dfcbc4e611ab5fafbe from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 4e5ec9c0dc
target/arm: Factor MPU lookup code out of get_phys_addr_pmsav8()
For the TT instruction we're going to need to do an MPU lookup that
also tells us which MPU region the access hit. This requires us
to do the MPU lookup without first doing the SAU security access
check, so pull the MPU lookup parts of get_phys_addr_pmsav8()
out into their own function.

The TT instruction also needs to know the MPU region number which
the lookup hit, so provide this information to the caller of the
MPU lookup code, even though get_phys_addr_pmsav8() doesn't
need to know it.

Backports commit 54317c0ff3a3c0f6b2c3a1d3c8b5d93686a86d24 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell c441b19d76
target/arm: Create new arm_v7m_mmu_idx_for_secstate_and_priv()
The TT instruction is going to need to look up the MMU index
for a specified security and privilege state. Refactor the
existing arm_v7m_mmu_idx_for_secstate() into a version that
lets you specify the privilege state and one that uses the
current state of the CPU.

Backports commit ec8e3340286a87d3924c223d60ba5c994549f796 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 89acdeb9af
target/arm: Split M profile MNegPri mmu index into user and priv
For M profile, we currently have an mmu index MNegPri for
"requested execution priority negative". This fails to
distinguish "requested execution priority negative, privileged"
from "requested execution priority negative, usermode", but
the two can return different results for MPU lookups. Fix this
by splitting MNegPri into MNegPriPriv and MNegPriUser, and
similarly for the Secure equivalent MSNegPri.

This takes us from 6 M profile MMU modes to 8, which means
we need to bump NB_MMU_MODES; this is OK since the point
where we are forced to reduce TLB sizes is 9 MMU modes.

(It would in theory be possible to stick with 6 MMU indexes:
{mpu-disabled,user,privileged} x {secure,nonsecure} since
in the MPU-disabled case the result of an MPU lookup is
always the same for both user and privileged code. However
we would then need to rework the TB flags handling to put
user/priv into the TB flags separately from the mmuidx.
Adding an extra couple of mmu indexes is simpler.)

Backports commit 62593718d77c06ad2b5e942727cead40775d2395 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell d877985eea
target/arm: Add missing M profile case to regime_is_user()
When we added the ARMMMUIdx_MSUser MMU index we forgot to
add it to the case statement in regime_is_user(), so we
weren't treating it as unprivileged when doing MPU lookups.
Correct the omission.

Backports commit 871bec7c44a453d9cab972ce1b5d12e1af0545ab from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 999080382f
target/arm: Allow explicit writes to CONTROL.SPSEL in Handler mode
In ARMv7M the CPU ignores explicit writes to CONTROL.SPSEL
in Handler mode. In v8M the behaviour is slightly different:
writes to the bit are permitted but will have no effect.

We've already done the hard work to handle the value in
CONTROL.SPSEL being out of sync with what stack pointer is
actually in use, so all we need to do to fix this last loose
end is to update the condition we use to guard whether we
call write_v7m_control_spsel() on the register write.

Backports commit 83d7f86d3d27473c0aac79c1baaa5c2ab01b02d9 from qemu
2018-03-05 13:48:30 -05:00
Peter Maydell 6713884243
target/arm: Handle SPSEL and current stack being out of sync in MSP/PSP reads
For v8M it is possible for the CONTROL.SPSEL bit value and the
current stack to be out of sync. This means we need to update
the checks used in reads and writes of the PSP and MSP special
registers to use v7m_using_psp() rather than directly checking
the SPSEL bit in the control register.

Backports commit 1169d3aa5b19adca9384d954d80e1f48da388284 from qemu
2018-03-05 13:48:30 -05:00
Eduardo Habkost 64a535ea8c
i386: Add EPYC-IBPB CPU model
EPYC-IBPB is a copy of the EPYC CPU model with
just CPUID_8000_0008_EBX_IBPB added.

Backports commit 8ebfafa796ca0cb2b035a7f06f836a675d8b48be from qemu
2018-03-05 13:48:30 -05:00
Eduardo Habkost 676409d54e
i386: Add new -IBRS versions of Intel CPU models
The new MSR IA32_SPEC_CTRL MSR was introduced by a recent Intel
microcode updated and can be used by OSes to mitigate
CVE-2017-5715. Unfortunately we can't change the existing CPU
models without breaking existing setups, so users need to
explicitly update their VM configuration to use the new *-IBRS
CPU model if they want to expose IBRS to guests.

The new CPU models are simple copies of the existing CPU models,
with just CPUID_7_0_EDX_SPEC_CTRL added and model_id updated.

Backports commit 61efbbf869293f1deb9ee39d44bd4e635de59fa7 from qemu
2018-03-05 13:48:30 -05:00
Eduardo Habkost 6fbabb4bce
i386: Add FEAT_8000_0008_EBX CPUID feature word
Add the new feature word and the "ibpb" feature flag.

Based on a patch by Paolo Bonzini.

Backports commit 1ade973f5202404e772aae7b1acd331270d246dc from qemu
2018-03-05 13:48:30 -05:00
Eduardo Habkost 7bee95ad28
i386: Add spec-ctrl CPUID bit
Add the feature name and a CPUID_7_0_EDX_SPEC_CTRL macro.

Backports commit 803d42fa65a371f7bb13180a5953299dc3a160e0 from qemu
2018-03-05 13:48:30 -05:00
Paolo Bonzini 7cf98b1a6e
i386: Add support for SPEC_CTRL MSR
Backports commit cb2637a5ae1f4e61af423395300548f14e8a2e2a from qemu
2018-03-05 13:48:29 -05:00
Eduardo Habkost 181524d695
i386: Change X86CPUDefinition::model_id to const char*
It is valid to have a 48-character model ID on CPUID, however the
definition of X86CPUDefinition::model_id is char[48], which can
make the compiler drop the null terminator from the string.

If a CPU model happens to have 48 bytes on model_id, "-cpu help"
will print garbage and the object_property_set_str() call at
x86_cpu_load_def() will read data outside the model_id array.

We could increase the array size to 49, but this would mean the
compiler would not issue a warning if a 49-char string is used by
mistake for model_id.

To make things simpler, simply change model_id to be const char*,
and validate the string length using an assert() on
x86_register_cpudef_type().

Backports commit 4b220d88ba76fb2623ce4b8ba1f1eea66b82144e from qemu
2018-03-05 13:48:29 -05:00
Peter Maydell d89704eb0f
target/i386: Fix handling of VEX prefixes
In commit e3af7c788b73a6495eb9d94992ef11f6ad6f3c56 we
replaced direct calls to to cpu_ld*_code() with calls
to the x86_ld*_code() wrappers which incorporate an
advance of s->pc. Unfortunately we didn't notice that
in one place the old code was deliberately not incrementing
s->pc:

@@ -4501,7 +4528,7 @@ static target_ulong disas_insn(DisasContext *s, CPUState *cpu)
static const int pp_prefix[4] = {
0, PREFIX_DATA, PREFIX_REPZ, PREFIX_REPNZ
};
- int vex3, vex2 = cpu_ldub_code(env, s->pc);
+ int vex3, vex2 = x86_ldub_code(env, s);

if (!CODE64(s) && (vex2 & 0xc0) != 0xc0) {
/* 4.1.4.6: In 32-bit mode, bits [7:6] must be 11b,

This meant we were mishandling this set of instructions.
Remove the manual advance of s->pc for the "is VEX" case
(which is now done by x86_ldub_code()) and instead rewind
PC in the case where we decide that this isn't really VEX.

Backports commit 817a9fcba8043faa467929e7b0193df6bdc92211 from qemu
2018-03-05 13:48:29 -05:00
Peter Maydell 352a7b2501
target/arm: Generate UNDEF for 32-bit Thumb2 insns
The refactoring of commit 296e5a0a6c3935 has a nasty bug:
it accidentally dropped the generation of code to raise
the UNDEF exception when disas_thumb2_insn() returns nonzero.
This means that 32-bit Thumb2 instruction patterns that
ought to UNDEF just act like nops instead. This is likely
to break any number of things, including the kernel's "disable
the FPU and use the UNDEF exception to identify when to turn
it back on again" trick.

Backports commit 7472e2efb049ea65a6a5e7261b78ebf5c561bc2f from qemu
2018-03-05 13:48:29 -05:00
Peter Maydell 6285ed170e
osdep.h: Make TIME_MAX handle different time_t types
In our various supported host OSes, the time_t type may be either 32
or 64 bit, and could in theory also be either signed or unsigned.
Notably, in OpenBSD time_t is a 64 bit type even if 'long' is 32
bits, so using LONG_MAX for TIME_MAX is incorrect.

Use an approach suggested by Paolo Bonzini which calculates
the maximum value of the type rather than hardcoding it;
to do this we use the TYPE_MAXIMUM macro from Gnulib.

Backports commit e7b47c22e2df14d55e3e4426688c929bf8e3f7fb from qemu
2018-03-05 13:48:29 -05:00
Peter Maydell c01b9a3cfe
arm: check regime, not current state, for ATS write PAR format
In do_ats_write(), rather than using extended_addresses_enabled() to
decide whether the value we get back from get_phys_addr() is a 64-bit
format PAR or a 32-bit one, use arm_s1_regime_using_lpae_format().

This is not really the correct answer, because the PAR format
depends on the AT instruction being used, not just on the
translation regime. However getting this correct requires a
significant refactoring, so that get_phys_addr() returns raw
information about the fault which the caller can then assemble
into a suitable FSR/PAR/syndrome for its purposes, rather than
get_phys_addr() returning a pre-formatted FSR.

However this change at least improves the situation by making
the PAR work correctly for address translation operations done
at AArch64 EL2 on the EL2 translation regime. In particular,
this is necessary for Xen to be able to run in our emulation,
so this seems like a safer interim fix given that we are in freeze.

Backports commit 50cd71b0d347c74517dcb7da447fe657fca57d9c from qemu
2018-03-05 13:48:28 -05:00
Peter Maydell 175b632c91
target/arm: Report GICv3 sysregs present in ID registers if needed
The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
have a field for reporting presence of GICv3 system registers.
We need to report this field correctly in order for Xen to
work as a guest inside QEMU emulation. We mustn't incorrectly
claim the sysregs exist when they don't, though, or Linux will
crash.

Unfortunately the way we've designed the GICv3 emulation in QEMU
puts the system registers as part of the GICv3 device, which
may be created after the CPU proper has been realized. This
means that we don't know at the point when we define the ID
registers what the correct value is. Handle this by switching
them to calling a function at runtime to read the value, where
we can fill in the GIC field appropriately.

Backports commit 96a8b92ed8f02d5e86ad380d3299d9f41f99b072 from qemu
2018-03-05 13:48:28 -05:00
Wanpeng Li 72430e4d75
target-i386: adds PV_TLB_FLUSH CPUID feature bit
Adds PV_TLB_FLUSH CPUID feature bit.

Backports commit 6976af663d3a19d1f86a56b5504f1b4559d0f1ae from qemu
2018-03-05 13:48:28 -05:00
Richard Henderson a58eb310eb
target/arm: Use helper_retaddr in stxp helpers
We use raw memory primitives along the !parallel_cpus paths in order to
simplify the endianness handling. Because of that, we did not benefit
from the generic changes to cpu_ldst_user_only_template.h.

The simplest fix is to manipulate helper_retaddr here.

Backports commit 3bdb5fcc9a08a9a47ce30c4e0c2d64c95190b49d from qemu
2018-03-05 13:48:28 -05:00
Richard Henderson f76eb22a46
tcg: Record code_gen_buffer address for user-only memory helpers
When we handle a signal from a fault within a user-only memory helper,
we cannot cpu_restore_state with the PC found within the signal frame.
Use a TLS variable, helper_retaddr, to record the unwind start point
to find the faulting guest insn.

Backports commit ec603b5584fa71213ef8f324fe89e4b27cc9d2bc from qemu
2018-03-05 13:48:28 -05:00
Lioncash 7ec1f12429
compiler: Add defines for abstracting thread-local storage 2018-03-05 13:48:27 -05:00
Richard Henderson 9f0393479e
tcg: Record code_gen_buffer address for user-only memory helpers
When we handle a signal from a fault within a user-only memory helper,
we cannot cpu_restore_state with the PC found within the signal frame.
Use a TLS variable, helper_retaddr, to record the unwind start point
to find the faulting guest insn.

Backports commit ec603b5584fa71213ef8f324fe89e4b27cc9d2bc from qemu
2018-03-05 13:48:27 -05:00
Emilio G. Cota 208014df9e
arm/translate-a64: mark path as unreachable to eliminate warning
Fixes the following warning when compiling with gcc 5.4.0 with -O1
optimizations and --enable-debug:

target/arm/translate-a64.c: In function ‘aarch64_tr_translate_insn’:
target/arm/translate-a64.c:2361:8: error: ‘post_index’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (!post_index) {
^
target/arm/translate-a64.c:2307:10: note: ‘post_index’ was declared here
bool post_index;
^
target/arm/translate-a64.c:2386:8: error: ‘writeback’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (writeback) {
^
target/arm/translate-a64.c:2308:10: note: ‘writeback’ was declared here
bool writeback;
^

Note that idx comes from selecting 2 bits, and therefore its value
can be at most 3.

Backports commit 5ca66278c859bb1ded243755aeead2be6992ce73 from qemu
2018-03-05 11:40:11 -05:00
Peter Maydell 33d42df60c
translate.c: Fix usermode big-endian AArch32 LDREXD and STREXD
For AArch32 LDREXD and STREXD, architecturally the 32-bit word at the
lowest address is always Rt and the one at addr+4 is Rt2, even if the
CPU is big-endian. Our implementation does these with a single
64-bit store, so if we're big-endian then we need to put the two
32-bit halves together in the opposite order to little-endian,
so that they end up in the right places. We were trying to do
this with the gen_aa32_frob64() function, but that is not correct
for the usermode emulator, because there there is a distinction
between "load a 64 bit value" (which does a BE 64-bit access
and doesn't need swapping) and "load two 32 bit values as one
64 bit access" (where we still need to do the swapping, like
system mode BE32).

Backports commit 3448d47b3172015006b79197eb5a69826c6a7b6d from qemu
2018-03-05 11:39:29 -05:00
Andrew Baumann 5250db33b5
arm: implement cache/shareability attribute bits for PAR registers
On a successful address translation instruction, PAR is supposed to
contain cacheability and shareability attributes determined by the
translation. We previously returned 0 for these bits (in line with the
general strategy of ignoring caches and memory attributes), but some
guest OSes may depend on them.

This patch collects the attribute bits in the page-table walk, and
updates PAR with the correct attributes for all LPAE translations.
Short descriptor formats still return 0 for these bits, as in the
prior implementation.

Backports commit 5b2d261d60caf9d988d91ca1e02392d6fc8ea104 from qemu
2018-03-05 11:35:28 -05:00
Paolo Bonzini 5216dcd157
build: disable -Wmissing-braces on older compilers
GCC 4.9 and newer stopped warning for missing braces around the
"universal" C zero initializer {0}. One such initializer sneaked
into scsi/qemu-pr-helper.c and is breaking the build with such
older GCC versions.

Detect the lack of support for the idiom, and disable the warning
in that case.

Backports commit 20bc94a2b8449b7700b6bfa25a87ce2320a1c649 from qemu
2018-03-05 11:29:54 -05:00
Richard Henderson 5ef155a68f
tcg/s390x: Use constant pool for prologue
Rather than have separate code only used for guest_base,
rely on a recent change to handle constant pool entries.

Backports commit ba2c747992f8c315c2fbddba196ce9137430d61d from qemu
2018-03-05 11:28:39 -05:00
Richard Henderson ef3f552229
tcg: Allow constant pool entries in the prologue
Both ARMv6 and AArch64 currently may drop complex guest_base values
into the constant pool. But generic code wasn't expecting that, and
the pool is not emitted. Correct that.

Backports commit 5b38ee31616d1532c3c3a6dc644a9160d608ed2f from qemu
2018-03-05 11:25:56 -05:00
Stefano Stabellini 1212c9b73c
fix WFI/WFE length in syndrome register
WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.

Pass the instruction length to HELPER(wfi), use it to decrement pc
appropriately and to pass an is_16bit flag to syn_wfx, which sets
ARM_EL_IL_SHIFT if needed.

Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.

Backports commit 58803318e5a546b2eb0efd7a053ed36b6c29ae6f from qemu
2018-03-05 11:21:51 -05:00
Richard Henderson ab9df6244c
tcg: Use offsets not indices for TCGv_*
Using the offset of a temporary, relative to TCGContext, rather than
its index means that we don't use 0. That leaves offset 0 free for
a NULL representation without having to leave index 0 unused.

Backports commit e89b28a63501c0ad6d2501fe851d0c5202055e70 from qemu
2018-03-05 10:12:08 -05:00
Richard Henderson 28061c2e59
qom: Introduce CPUClass.tcg_initialize
Move target cpu tcg initialization to common code,
called from cpu_exec_realizefn.

Backports commit 55c3ceef61fcf06fc98ddc752b7cce788ce7680b from qemu
2018-03-05 09:49:26 -05:00
Richard Henderson 4d9c8583fa
tcg: Remove TCGV_EQUAL*
When we used structures for TCGv_*, we needed a macro in order to
perform a comparison. Now that we use pointers, this is just clutter

Backports commit 11f4e8f8bfaa2caaab24bef6bbbb8a0205015119 from qemu
2018-03-05 09:16:07 -05:00
Richard Henderson d450156414
tcg: Remove GET_TCGV_* and MAKE_TCGV_*
The GET and MAKE functions weren't really specific enough.
We now have a full complement of functions that convert exactly
between temporaries, arguments, tcgv pointers, and indices.

The target/sparc change is also a bug fix, which would have affected
a host that defines TCG_TARGET_HAS_extr[lh]_i64_i32, i.e. MIPS64.

Backports commit dc41aa7d34989b552efe712ffe184236216f960b from qemu
2018-03-05 09:12:26 -05:00
Richard Henderson 960eb3f4f9
tcg: Introduce temp_tcgv_{i32,i64,ptr}
Backports commit 085272b35e0644fea373c33b5265c1818b7a978c from qemu
2018-03-05 08:55:52 -05:00
Richard Henderson 2bb5011b18
tcg: Introduce tcgv_{i32,i64,ptr}_{arg,temp}
Transform TCGv_* to an "argument" or a temporary.
For now, an argument is simply the temporary index.

Backports commit ae8b75dc6ec808378487064922f25f1e7ea7a9be from qemu
2018-03-05 08:46:12 -05:00
Richard Henderson 9f8c6a456b
tcg: Use per-temp state data in optimize
While we're touching many of the lines anyway, adjust the naming
of the functions to better distinguish when "TCGArg" vs "TCGTemp"
should be used.

Backports commit 6349039d0b06eda59820629b934944246b14a1c1 from qemu
2018-03-05 08:24:06 -05:00
Richard Henderson 387060ccf5
tcg: Remove unused TCG_CALL_DUMMY_TCGV
Backports commit 54534d7cfd3bdff1aa1f6c9472d94243d2303656 from qemu
2018-03-05 07:52:35 -05:00
Richard Henderson d104b792a6
tcg: Change temp_allocate_frame arg to TCGTemp
Backports commit 2272e4a791b7e1a01ffac143616ba4ece9a5762d from qemu
2018-03-05 07:51:40 -05:00
Richard Henderson 35a7a9c9a4
tcg: Avoid loops against variable bounds
Copy s->nb_globals or s->nb_temps to a local variable for the purposes
of iteration. This should allow the compiler to use low-overhead
looping constructs on some hosts.

Backports commit ac3b88911ebc6fc841f28898ee8aed40839debe2 from qemu
2018-03-05 07:50:06 -05:00
Richard Henderson 1f4ac863bf
tcg: Use per-temp state data in liveness
This avoids having to allocate external memory for each temporary.

Backports commit b83eabeac06e38706738bd5e92b1ba117a1b554d from qemu
2018-03-05 07:47:51 -05:00