Mips16 is really a processor decoding mode (ala thumb 1) and in the same
program, mips16 and mips32 functions can exist and can call each other.
If a jal type instruction encounters an address with the lower bit set, then
the processor switches to mips16 mode (if it is not already in it). If the
lower bit is not set, then it switches to mips32 mode.
The linker knows which functions are mips16 and which are mips32.
When relocation is performed on code labels, this lower order bit is
set if the code label is a mips16 code label.
In general this works just fine, however when creating exception handling
tables and dwarf, there are cases where you don't want this lower order
bit added in.
This has been traditionally distinguished in gas assembly source by using a
different syntax for the label.
lab1: ; this will cause the lower order bit to be added
lab2=. ; this will not cause the lower order bit to be added
In some cases, it does not matter because in dwarf and debug tables
the difference of two labels is used and in that case the lower order
bits subtract each other out.
To fix this, I have added to mcstreamer the notion of a debuglabel.
The default is for label and debug label to be the same. So calling
EmitLabel and EmitDebugLabel produce the same result.
For various reasons, there is only one set of labels that needs to be
modified for the mips exceptions to work. These are the "$eh_func_beginXXX"
labels.
Mips overrides the debug label suffix from ":" to "=." .
This initial patch fixes exceptions. More changes most likely
will be needed to DwarfCFException to make all of this work
for actual debugging. These changes will be to emit debug labels in some
places where a simple label is emitted now.
Some historical discussion on this from gcc can be found at:
http://gcc.gnu.org/ml/gcc-patches/2008-08/msg00623.htmlhttp://gcc.gnu.org/ml/gcc-patches/2008-11/msg01273.html
llvm-svn: 170279
In this case, essentially it is soft float with different library routines.
The next step will be to make this fully interoperational with mips32 floating
point and that requires creating stubs for functions with signatures that
contain floating point types.
I have a more sophisticated design for mips16 hardfloat which I hope to
implement at a later time that directly does floating point without the need
for function calls.
The mips16 encoding has no floating point instructions so one needs to
switch to mips32 mode to execute floating point instructions.
llvm-svn: 170259
We will make them delay slot forms if there is something that can be
placed in the delay slot during a separate pass. Mips16 extended instructions
cannot be placed in delay slots.
llvm-svn: 166990
Previously mips16 was sharing the pattern addr which is used for mips32
and mips64. This had a number of problems:
1) Storing and loading byte and halfword quantities for mips16 has particular
problems due to the primarily non mips16 nature of SP. When we must
load/store byte/halfword stack objects in a function, we must create a mips16
alias register for SP. This functionality is tested in stchar.ll.
2) We need to have an FP register under certain conditions (such as
dynamically sized alloca). We use mips16 register S0 for this purpose.
In this case, we also use this register when accessing frame objects so this
issue also affects the complex pattern addr16. This functionality is
tested in alloca16.ll.
The Mips16InstrInfo.td has been updated to use addr16 instead of addr.
The complex pattern C++ function for addr has been copied to addr16 and
updated to reflect the above issues.
llvm-svn: 166897
Instructions emitted to compute branch offsets now use immediate operands
instead of symbolic labels. This change was needed because there were problems
when R_MIPS_HI16/LO16 relocations were used to make shared objects.
llvm-svn: 162731
In SelectionDAGLegalize::ExpandLegalINT_TO_FP, expand INT_TO_FP nodes without
using any f64 operations if f64 is not a legal type.
Patch by Stefan Kristiansson.
llvm-svn: 162728
MipsSEFrameLowering.
Implement MipsSEFrameLowering::hasReservedCallFrame. Call frames will not be
reserved if there is a call with a large call frame or there are variable sized
objects on the stack.
llvm-svn: 161090
The frame object which points to the dynamically allocated area will not be
needed after changes are made to cease reserving call frames.
llvm-svn: 161076
arguments to the stack in MipsISelLowering::LowerCall, use stack pointer and
integer offset operands rather than frame object operands.
llvm-svn: 161068
single-precision load and store.
Also avoid selecting LUXC1 and SUXC1 instructions during isel. It is incorrect
to map unaligned floating point load/store nodes to these instructions.
llvm-svn: 161063
The long branch pass (fixed in r160601) no longer uses the global base register
to compute addresses of branch destinations, so it is not necessary to reserve
a slot on the stack.
llvm-svn: 160703
This pass no longer requires that the global pointer value be saved to the
stack or register since it uses bal instruction to compute branch distance.
llvm-svn: 160601
Print the high order register of a double word register operand.
In 32 bit mode, a 64 bit double word integer will be represented
by 2 32 bit registers. This modifier causes the high order register
to be used in the asm expression. It is useful if you are using
doubles in assembler and continue to control register to variable
relationships.
This patch also fixes a related bug in a previous patch:
case 'D': // Second part of a double word register operand
case 'L': // Low order register of a double word register operand
case 'M': // High order register of a double word register operand
I got 'D' and 'M' confused. The second part of a double word operand
will only match 'M' for one of the endianesses. I had 'L' and 'D'
be the opposite twins when 'L' and 'M' are.
llvm-svn: 160429
Low order register of a double word register operand. Operands
are defined by the name of the variable they are marked with in
the inline assembler code. This is a way to specify that the
operand just refers to the low order register for that variable.
It is the opposite of modifier 'D' which specifies the high order
register.
Example:
main()
{
long long ll_input = 0x1111222233334444LL;
long long ll_val = 3;
int i_result = 0;
__asm__ __volatile__(
"or %0, %L1, %2"
: "=r" (i_result)
: "r" (ll_input), "r" (ll_val));
}
Which results in:
lui $2, %hi(_gp_disp)
addiu $2, $2, %lo(_gp_disp)
addiu $sp, $sp, -8
addu $2, $2, $25
sw $2, 0($sp)
lui $2, 13107
ori $3, $2, 17476 <-- Low 32 bits of ll_input
lui $2, 4369
ori $4, $2, 8738 <-- High 32 bits of ll_input
addiu $5, $zero, 3 <-- Low 32 bits of ll_val
addiu $2, $zero, 0 <-- High 32 bits of ll_val
#APP
or $3, $4, $5 <-- or i_result, high 32 ll_input, low 32 of ll_val
#NO_APP
addiu $sp, $sp, 8
jr $ra
If not direction is done for the long long for 32 bit variables results
in using the low 32 bits as ll_val shows.
There is an existing bug if 'L' or 'D' is used for the destination register
for 32 bit long longs in that the target value will be updated incorrectly
for the non-specified part unless explicitly set within the inline asm code.
llvm-svn: 160028
Print the second half of a double word operand.
The include list was cleaned up a bit as well.
Also the test case was modified to test for both
big and little patterns.
llvm-svn: 159787
inlineasm-cnstrnt-bad-r-1.ll is NOT supposed to fail, so it was removed. This resulted in the removal of a negative test (inlineasm-cnstrnt-bad-r-1.ll)
llvm-svn: 159625
inlineasm-cnstrnt-bad-r-1.ll is NOT supposed to fail, so it was removed. This resulted in the removal of a negative test (inlineasm-cnstrnt-bad-r-1.ll)
llvm-svn: 159610
another mechanical change accomplished though the power of terrible Perl
scripts.
I have manually switched some "s to 's to make escaping simpler.
While I started this to fix tests that aren't run in all configurations,
the massive number of tests is due to a really frustrating fragility of
our testing infrastructure: things like 'grep -v', 'not grep', and
'expected failures' can mask broken tests all too easily.
Essentially, I'm deeply disturbed that I can change the testsuite so
radically without causing any change in results for most platforms. =/
llvm-svn: 159547
This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as
@x = thread_local(initialexec) global i32 42
if it will not be used in a shared library that is dlopen'ed.
If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.
llvm-svn: 159077
to be generic across architectures. It has the
following description in the gnu sources:
Negate the immediate constant
Several Architectures such as x86 have local implementations
of operand modifier 'n' which go beyond the above description
slightly. This won't affect them.
Affected files:
lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
Added 'n' to the switch cases.
test/CodeGen/Generic/asm-large-immediate.ll
Generic compiled test (x86 for me)
test/CodeGen/Mips/asm-large-immediate.ll
Mips compiled version of the generic one
Contributer: Jack Carter
llvm-svn: 158939
to be generic across architectures. It has the
following description in the gnu sources:
Substitute immediate value without immediate syntax
Several Architectures such as x86 have local implementations
of operand modifier 'c' which go beyond the above description
slightly. To make use of the generic modifiers without overriding
local implementation one can make a call to the base class method
for AsmPrinter::PrintAsmOperand() in the locally derived method's
"default" case in the switch statement. That way if it is already
defined locally the generic version will never get called.
This change is needed when test/CodeGen/generic/asm-large-immediate.ll
failed on a native Mips board. The test was assuming a generic
implementation was in place.
Affected files:
lib/Target/Mips/MipsAsmPrinter.cpp:
Changed the default case to call the base method.
lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp
Added 'c' to the switch cases.
test/CodeGen/Mips/asm-large-immediate.ll
Mips compiled version of the generic one
Contributer: Jack Carter
llvm-svn: 158925
- Remove code which lowers pseudo SETGP01.
- Fix LowerSETGP01. The first two of the three instructions that are emitted to
initialize the global pointer register now use register $2.
- Stop emitting .cpload directive.
llvm-svn: 156689
pointer register.
This is the first of the series of patches which clean up the way global pointer
register is used. The patches will make the following improvements:
- Make $gp an allocatable temporary register rather than reserving it.
- Use a virtual register as the global pointer register and let the register
allocator decide which register to assign to it or whether spill/reloads are
needed.
- Make sure $gp is valid at the entry of a called function, which is necessary
for functions using lazy binding.
- Remove the need for emitting .cprestore and .cpload directives.
llvm-svn: 156671
This is mostly to test the waters. I'd like to get results from FNT
build bots and other bots running on non-x86 platforms.
This feature has been pretty heavily tested over the last few months by
me, and it fixes several of the execution time regressions caused by the
inlining work by preventing inlining decisions from radically impacting
block layout.
I've seen very large improvements in yacr2 and ackermann benchmarks,
along with the expected noise across all of the benchmark suite whenever
code layout changes. I've analyzed all of the regressions and fixed
them, or found them to be impossible to fix. See my email to llvmdev for
more details.
I'd like for this to be in 3.1 as it complements the inliner changes,
but if any failures are showing up or anyone has concerns, it is just
a flag flip and so can be easily turned off.
I'm switching it on tonight to try and get at least one run through
various folks' performance suites in case SPEC or something else has
serious issues with it. I'll watch bots and revert if anything shows up.
llvm-svn: 154816
- FCOPYSIGN nodes that have operands of different types were not handled.
- Different code was generated depending on the endianness of the target.
Additionally, code is added that emits INS and EXT instructions, if they are
supported by target (they are R2 instructions).
llvm-svn: 154540
* Removed test/lib/llvm.exp - it is no longer needed
* Deleted the dg.exp reading code from test/lit.cfg. There are no dg.exp files
left in the test suite so this code is no longer required. test/lit.cfg is
now much shorter and clearer
* Removed a lot of duplicate code in lit.local.cfg files that need access to
the root configuration, by adding a "root" attribute to the TestingConfig
object. This attribute is dynamically computed to provide the same
information as was previously provided by the custom getRoot functions.
* Documented the config.root attribute in docs/CommandGuide/lit.pod
llvm-svn: 153408
and stores was added.
- SelectAddr should return false if Parent is an unaligned f32 load or store.
- Only aligned load and store nodes should be matched to select reg+imm
floating point instructions.
- MIPS does not have support for f64 unaligned load or store instructions.
llvm-svn: 151843
reserving a physical register ($gp or $28) for that purpose.
This will completely eliminate loads that restore the value of $gp after every
function call, if the register allocator assigns a callee-saved register, or
eliminate unnecessary loads if it assigns a temporary register.
example:
.cpload $25 // set $gp.
...
.cprestore 16 // store $gp to stack slot 16($sp).
...
jalr $25 // function call. clobbers $gp.
lw $gp, 16($sp) // not emitted if callee-saved reg is chosen.
...
lw $2, 4($gp)
...
jalr $25 // function call.
lw $gp, 16($sp) // not emitted if $gp is not live after this instruction.
...
llvm-svn: 151402
needed to emit a 64-bit gp-relative relocation entry. Make changes necessary
for emitting jump tables which have entries with directive .gpdword. This patch
does not implement the parts needed for direct object emission or JIT.
llvm-svn: 149668
- Use MipsAnalyzeImmediate to expand immediates that do not fit in 16-bit.
- Change the types of variables so that they are sufficiently large to handle
64-bit pointers.
- Emit instructions to set register $28 in a function prologue after
instructions which store callee-saved registers have been emitted.
llvm-svn: 148917
This change reduces the number of instructions generated.
For example,
(load (add (sub $n0, $n1), (MipsLo got(s))))
results in the following sequence of instructions:
1. sub $n2, $n0, $n1
2. lw got(s)($n2)
Previously, three instructions were needed.
1. sub $n2, $n0, $n1
2. addiu $n3, $n2, got(s)
3. lw 0($n3)
llvm-svn: 146888
test cases where there were a lot of relocations applied relative to a large
rodata section. Gas would create a symbol for each of these whereas we would
be relative to the beginning of the rodata section. This change mimics what
gas does.
Patch by Jack Carter.
llvm-svn: 146468
I followed three heuristics for deciding whether to set 'true' or
'false':
- Everything target independent got 'true' as that is the expected
common output of the GCC builtins.
- If the target arch only has one way of implementing this operation,
set the flag in the way that exercises the most of codegen. For most
architectures this is also the likely path from a GCC builtin, with
'true' being set. It will (eventually) require lowering away that
difference, and then lowering to the architecture's operation.
- Otherwise, set the flag differently dependending on which target
operation should be tested.
Let me know if anyone has any issue with this pattern or would like
specific tests of another form. This should allow the x86 codegen to
just iteratively improve as I teach the backend how to differentiate
between the two forms, and everything else should remain exactly the
same.
llvm-svn: 146370
fixes: Use a separate register, instead of SP, as the
calling-convention resource, to avoid spurious conflicts with
actual uses of SP. Also, fix unscheduling of calling sequences,
which can be triggered by pseudo-two-address dependencies.
llvm-svn: 143206
it fixes the dragonegg self-host (it looks like gcc is miscompiled).
Original commit messages:
Eliminate LegalizeOps' LegalizedNodes map and have it just call RAUW
on every node as it legalizes them. This makes it easier to use
hasOneUse() heuristics, since unneeded nodes can be removed from the
DAG earlier.
Make LegalizeOps visit the DAG in an operands-last order. It previously
used operands-first, because LegalizeTypes has to go operands-first, and
LegalizeTypes used to be part of LegalizeOps, but they're now split.
The operands-last order is more natural for several legalization tasks.
For example, it allows lowering code for nodes with floating-point or
vector constants to see those constants directly instead of seeing the
lowered form (often constant-pool loads). This makes some things
somewhat more complicated today, though it ought to allow things to be
simpler in the future. It also fixes some bugs exposed by Legalizing
using RAUW aggressively.
Remove the part of LegalizeOps that attempted to patch up invalid chain
operands on libcalls generated by LegalizeTypes, since it doesn't work
with the new LegalizeOps traversal order. Instead, define what
LegalizeTypes is doing to be correct, and transfer the responsibility
of keeping calls from having overlapping calling sequences into the
scheduler.
Teach the scheduler to model callseq_begin/end pairs as having a
physical register definition/use to prevent calls from having
overlapping calling sequences. This is also somewhat complicated, though
there are ways it might be simplified in the future.
This addresses rdar://9816668, rdar://10043614, rdar://8434668, and others.
Please direct high-level questions about this patch to management.
Delete #if 0 code accidentally left in.
llvm-svn: 143188
on every node as it legalizes them. This makes it easier to use
hasOneUse() heuristics, since unneeded nodes can be removed from the
DAG earlier.
Make LegalizeOps visit the DAG in an operands-last order. It previously
used operands-first, because LegalizeTypes has to go operands-first, and
LegalizeTypes used to be part of LegalizeOps, but they're now split.
The operands-last order is more natural for several legalization tasks.
For example, it allows lowering code for nodes with floating-point or
vector constants to see those constants directly instead of seeing the
lowered form (often constant-pool loads). This makes some things
somewhat more complicated today, though it ought to allow things to be
simpler in the future. It also fixes some bugs exposed by Legalizing
using RAUW aggressively.
Remove the part of LegalizeOps that attempted to patch up invalid chain
operands on libcalls generated by LegalizeTypes, since it doesn't work
with the new LegalizeOps traversal order. Instead, define what
LegalizeTypes is doing to be correct, and transfer the responsibility
of keeping calls from having overlapping calling sequences into the
scheduler.
Teach the scheduler to model callseq_begin/end pairs as having a
physical register definition/use to prevent calls from having
overlapping calling sequences. This is also somewhat complicated, though
there are ways it might be simplified in the future.
This addresses rdar://9816668, rdar://10043614, rdar://8434668, and others.
Please direct high-level questions about this patch to management.
llvm-svn: 143177
