that push immediate operands of 1, 2, and 4 bytes (extended to the native
register size in each case). The assembly mnemonics are "pushl" and "pushq."
One such instruction appears at the beginning of the "start" function , so this
is essential for accurate disassembly when unwinding."
Patch by Sean Callanan!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73407 91177308-0d34-0410-b5e6-96231b3b80d8
specific one. The GNU one is chosen when _GNU_SOURCE is defined. g++ always
defines _GNU_SOURCE on linux platforms because glibc's headers won't compile
in C++ mode without it. The GNU strerror_r doesn't always modify the buffer
which causes empty error messages on linux.
This patch changes MakeErrMsg to use the return value of strerror_r to get
the string instead of assuming the buffer will be modified, on GLIBC.
Patch by Benjamin Kramer!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73396 91177308-0d34-0410-b5e6-96231b3b80d8
incomming chain of the RETURN node. The incomming chain must
be the outgoing chain of the CALL node. This causes the
backend to identify tail calls that are not tail calls. This
patch fixes this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73387 91177308-0d34-0410-b5e6-96231b3b80d8
Look for as in the path. Doing it here instead
of llvm-gcc because llvm-gcc has nothing as
convenient as sys::Program::FindProgramByName.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73383 91177308-0d34-0410-b5e6-96231b3b80d8
- Change register allocation hint to a pair of unsigned integers. The hint type is zero (which means prefer the register specified as second part of the pair) or entirely target dependent.
- Allow targets to specify alternative register allocation orders based on allocation hint.
Part 2.
- Use the register allocation hint system to implement more aggressive load / store multiple formation.
- Aggressively form LDRD / STRD. These are formed *before* register allocation. It has to be done this way to shorten live interval of base and offset registers. e.g.
v1025 = LDR v1024, 0
v1026 = LDR v1024, 0
=>
v1025,v1026 = LDRD v1024, 0
If this transformation isn't done before allocation, v1024 will overlap v1025 which means it more difficult to allocate a register pair.
- Even with the register allocation hint, it may not be possible to get the desired allocation. In that case, the post-allocation load / store multiple pass must fix the ldrd / strd instructions. They can either become ldm / stm instructions or back to a pair of ldr / str instructions.
This is work in progress, not yet enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73381 91177308-0d34-0410-b5e6-96231b3b80d8
they contain multiplications of constants with add operations.
This helps simplify several kinds of things; in particular it
helps simplify expressions like ((-1 * (%a + %b)) + %a) to %b,
as expressions like this often come up in loop trip count
computations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73361 91177308-0d34-0410-b5e6-96231b3b80d8
even though the order doesn't matter at the top level of an expression,
it does matter when the constant is a subexpression of an n-ary
expression, because n-ary expressions are sorted lexicographically.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73358 91177308-0d34-0410-b5e6-96231b3b80d8
is that, for functions whose bodies are entirely guarded by an if-statement, it
can be profitable to pull the test out of the callee and into the caller.
This code has had some cursory testing, but still has a number of known issues
on the LLVM test suite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73338 91177308-0d34-0410-b5e6-96231b3b80d8
induction variable when the addrec to be expanded does not require
a wider type. This eliminates the need for IndVarSimplify to
micro-manage SCEV expansions, because SCEVExpander now
automatically expands them in the form that IndVarSimplify considers
to be canonical. (LSR still micro-manages its SCEV expansions,
because it's optimizing for the target, rather than for
other optimizations.)
Also, this uses the new getAnyExtendExpr, which has more clever
expression simplification logic than the IndVarSimplify code it
replaces, and this cleans up some ugly expansions in code such as
the included masked-iv.ll testcase.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73294 91177308-0d34-0410-b5e6-96231b3b80d8
consecutive addresses togther. This makes it easier for the post-allocation pass
to form ldm / stm.
This is step 1. We are still missing a lot of ldm / stm opportunities because
of register allocation are not done in the desired order. More enhancements
coming.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73291 91177308-0d34-0410-b5e6-96231b3b80d8
of the target's pointer size. This avoids the need for -m32 on
the llvm-gcc command-line, which some targets may not support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73270 91177308-0d34-0410-b5e6-96231b3b80d8