If the extension of a loaded value is compared against zero and used in
other arithmetic, InstCombine will change the comparison to use the
unextended load. It's also possible that the comparison could be against
the unextended load from the outset.
In DAG form this becomes a truncation of an extending load. We want to
strip the truncation if possible so that we can use load-and-test instructions.
llvm-svn: 197804
The handling of ANY_EXTEND and ZERO_EXTEND was too strict. In this context
we can treat ZERO_EXTEND in much the same way as an AND and then also handle
outermost ZERO_EXTENDs.
I couldn't find a test that benefited from the ANY_EXTEND change, but it's
more obvious to write it this way once SIGN_EXTEND and ZERO_EXTEND are
handled differently.
llvm-svn: 197802
If we happen to eliminate every case in a switch that has branch
weights, we currently try to create metadata for the one remaining
branch, triggering an assert. Instead, we need to check that the
metadata we're trying to create is sensible.
llvm-svn: 197791
Since r197684, "install/bin/llvm-config --obj-root" hasn't shown the build tree. The builder was finding utils in the build tree, from the installed tree.
I will revert this after dragonegg builder would be tweaked not to use installed llvm-config.
llvm-svn: 197786
v2: Add ftrunc->TRUNC pattern instead of replacing int_AMDGPU_trunc
v3: move ftrunc pattern next to TRUNC definition, it's available since R600
Patch By: Jan Vesely
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
llvm-svn: 197783
when you want to have the full list of addresses for a particular CU or
when you have multiple modules linked together and can't depend upon the
ordering of a single CU for begin/end ranges.
llvm-svn: 197776
That's what it actually means, and with 16-bit support it's going to be
a little more relevant since in a few corner cases we may actually want
to distinguish between 16-bit and 32-bit mode (for example the bare 'push'
aliases to pushw/pushl etc.)
Patch by David Woodhouse
llvm-svn: 197768
this commit as the only one on the Blamelist so I quickly reverted this.
However it was actually Nick's change who has since fixed that issue.
Original commit message:
Changed the X86 assembler for intel syntax to work with directional labels.
The X86 assembler as a separate code to parser the intel assembly syntax
in X86AsmParser::ParseIntelOperand(). This did not parse directional labels.
And if something like 1f was used as a branch target it would get an
"Unexpected token" error.
The fix starts in X86AsmParser::ParseIntelExpression() in the case for
AsmToken::Integer, it needs to grab the IntVal from the current token
then look for a 'b' or 'f' following an Integer. Then it basically needs to
do what is done in AsmParser::parsePrimaryExpr() for directional
labels. It saves the MCExpr it creates in the IntelExprStateMachine
in the Sym field.
When it returns to X86AsmParser::ParseIntelOperand() it looks
for a non-zero Sym field in the IntelExprStateMachine and if
set it creates a memory operand not an immediate operand
it would normally do for the Integer.
rdar://14961158
llvm-svn: 197744
I have a pending change for clang to use getStringRepresentation to check
that its DataLayout is in sync with llvm's.
getStringRepresentation is not called from llvm itself, so far it is mostly
a debugging aid, so the shorter strings are an independent improvement.
llvm-svn: 197740
We dump any non-empty assembler constant pools after a successful
parse of an assembly file that uses the ldr pseudo opcode. These
per-section constant pools should be output in a deterministic order
to ensure that we always generate the same output when printing the
output with an AsmStreamer.
This patch changes the map data struture used to associate a section
with its constant pool to a MapVector to ensure deterministic
output. Because this map type does not support deletion, we now
check that the constant pool is not empty before dumping its entries
and clear the entries after emitting them with the streamer.
llvm-svn: 197735
The X86 assembler has a separate code to parser the intel assembly syntax
in X86AsmParser::ParseIntelOperand(). This did not parse directional labels.
And if something like 1f was used as a branch target it would get an
"Unexpected token" error.
The fix starts in X86AsmParser::ParseIntelExpression() in the case for
AsmToken::Integer, it needs to grab the IntVal from the current token
then look for a 'b' or 'f' following the Integer. Then it basically needs to
do what is done in AsmParser::parsePrimaryExpr() for directional
labels. It saves the MCExpr it creates in the IntelExprStateMachine
in the Sym field.
When it returns to X86AsmParser::ParseIntelOperand() it looks
for a non-zero Sym field in the IntelExprStateMachine and if
set it creates a memory operand not an immediate operand
it would normally do for the Integer.
rdar://14961158
llvm-svn: 197728
According to the docs, ThreadLocal<>::get() should return NULL
if no object has been set. This patch makes that the case also for non-thread
builds and adds a very basic unit test to check it.
(This was causing PR18205 because PrettyStackTraceHead didn't get zero-
initialized and we'd crash trying to read past the end of that list. We didn't
notice this so much on Linux since we'd crash after printing all the entries,
but on Mac we print into a SmallString, and would crash before printing that.)
llvm-svn: 197718
The condition in selects is supposed to be i1.
Make sure we are just reading the less significant bit
of the 8 bits width value to match this constraint.
<rdar://problem/15651765>
llvm-svn: 197712
This directive will write out the assembler-maintained constant
pool for the current section. These constant pools are created to
support the ldr-pseudo instruction (e.g. ldr r0, =val).
The directive can be used by the programmer to place the constant
pool in a location that can be reached by a pc-relative offset in
the ldr instruction.
llvm-svn: 197711
The ldr-pseudo opcode is a convenience for loading 32-bit constants.
It is converted into a pc-relative load from a constant pool. For
example,
ldr r0, =0x10001
ldr r1, =bar
will generate this output in the final assembly
ldr r0, .Ltmp0
ldr r1, .Ltmp1
...
.Ltmp0: .long 0x10001
.Ltmp1: .long bar
Sketch of the LDR pseudo implementation:
Keep a map from Section => ConstantPool
When parsing ldr r0, =val
parse val as an MCExpr
get ConstantPool for current Section
Label = CreateTempSymbol()
remember val in ConstantPool at next free slot
add operand to ldr that is MCSymbolRef of Label
On finishParse() callback
Write out all non-empty constant pools
for each Entry in ConstantPool
Emit Entry.Label
Emit Entry.Value
Possible improvements to be added in a later patch:
1. Does not convert load of small constants to mov
(e.g. ldr r0, =0x1 => mov r0, 0x1)
2. Does reuse constant pool entries for same constant
The implementation was tested for ARM, Thumb1, and Thumb2 targets on
linux and darwin.
llvm-svn: 197708
This callback is invoked when the parse has finished successfuly. It
will be used to write out ARM constant pools to implement the ldr
pseudo.
llvm-svn: 197706
This change fixes the case of arithmetic shift right - do not attempt to fold that case.
This change also relaxes the conditions when attempting to fold the logical shift right and shift left cases.
No additional IR-level test cases included at this time. See http://llvm.org/bugs/show_bug.cgi?id=17827 for proofs that these are correct transformations.
llvm-svn: 197705
The tests for the disassembler were adapted from the encoder tests, and for the
most part, the output from the disassembler matches that encoder-test inputs.
There are some places where more-informative mnemonics could be produced
(notably for the branch instructions), and those cases are noted in the tests
with FIXMEs.
Future work includes:
- Generating more-informative mnemonics when possible (this may also be done
in the printer).
- Remove the dependence on positional "numbered" operand-to-variable mapping
(for both encoding and decoding).
- Internally using 64-bit instruction variants in 64-bit mode (if this turns
out to matter).
llvm-svn: 197693
Unfortunately, the PowerPC instruction definitions make heavy use of the
positional operand encoding heuristic to map operands onto bitfield variables
in the instruction definitions. Changing this to use name-based mapping is not
trivial, however, because additional infrastructure needs to be designed to
handle mapping of complex operands (with multiple suboperands) onto multiple
bitfield variables.
In the mean time, this adds support for positionally encoded operands to
FixedLenDecoderEmitter, so that we can generate a disassembler for the PowerPC
backend. To prevent an accidental reliance on this feature, and to prevent an
undesirable interaction with existing disassemblers, a backend must opt-in to
this support by setting the new decodePositionallyEncodedOperands
instruction-set bit to true.
When enabled, this iterates the variables that contribute to the instruction
encoding, just as the encoder does, and emulates the procedure the encoder uses
to map "numbered" operands to variables. The bit range for each variable is
also determined as the encoder determines them. This map is then consulted
during the decoder-generator's loop over operands to decode, allowing the
decoder to understand both position-based and name-based operand-to-variable
mappings.
As noted in the comment on the decodePositionallyEncodedOperands definition,
this support should be removed once it is no longer needed. There should be no
change to existing disassemblers.
llvm-svn: 197691
