Allocate non-volatile registers in order to be compatible with ABI, regarding gpr_save.
Quoted from https://www.ibm.com/docs/en/ssw_aix_72/assembler/assembler_pdf.pdf page55,
> The preferred method of using GPRs is to use the volatile registers first. Next, use the nonvolatile registers
> in descending order, starting with GPR31.
This patch is based on @jsji 's initial draft.
Tested on test-suite and SPEC, found no degradation.
Reviewed By: jsji, ZarkoCA, xingxue
Differential Revision: https://reviews.llvm.org/D100167
This will currently accept the old number of bytes syntax, and convert
it to a scalar. This should be removed in the near future (I think I
converted all of the tests already, but likely missed a few).
Not sure what the exact syntax and policy should be. We can continue
printing the number of bytes for non-generic instructions to avoid
test churn and only allow non-scalar types for generic instructions.
This will currently print the LLT in parentheses, but accept parsing
the existing integers and implicitly converting to scalar. The
parentheses are a bit ugly, but the parser logic seems unable to deal
without either parentheses or some keyword to indicate the start of a
type.
SUMMARY:
1. in the patch , remove setting storageclass in function .getXCOFFSection and construct function of class MCSectionXCOFF
there are
XCOFF::StorageMappingClass MappingClass;
XCOFF::SymbolType Type;
XCOFF::StorageClass StorageClass;
in the MCSectionXCOFF class,
these attribute only used in the XCOFFObjectWriter, (asm path do not need the StorageClass)
we need get the value of StorageClass, Type,MappingClass before we invoke the getXCOFFSection every time.
actually , we can get the StorageClass of the MCSectionXCOFF from it's delegated symbol.
2. we also change the oprand of branch instruction from symbol name to qualify symbol name.
for example change
bl .foo
extern .foo
to
bl .foo[PR]
extern .foo[PR]
3. and if there is reference indirect call a function bar.
we also add
extern .bar[PR]
Reviewers: Jason liu, Xiangling Liao
Differential Revision: https://reviews.llvm.org/D84765
SUMMARY:
when we call memset, memcopy,memmove etc(this are llvm intrinsic function) in the c source code. the llvm will generate IR
like call call void @llvm.memset.p0i8.i32(i8* align 4 bitcast (%struct.S* @s to i8*), i8 %1, i32 %2, i1 false)
for c source code
bash> cat test_memset.call
struct S{
int a;
int b;
};
extern struct S s;
void bar() {
memset(&s, s.b, s.b);
}
like
%struct.S = type { i32, i32 }
@s = external global %struct.S, align 4
; Function Attrs: noinline nounwind optnone
define void @bar() #0 {
entry:
%0 = load i32, i32* getelementptr inbounds (%struct.S, %struct.S* @s, i32 0, i32 1), align 4
%1 = trunc i32 %0 to i8
%2 = load i32, i32* getelementptr inbounds (%struct.S, %struct.S* @s, i32 0, i32 1), align 4
call void @llvm.memset.p0i8.i32(i8* align 4 bitcast (%struct.S* @s to i8*), i8 %1, i32 %2, i1 false)
ret void
}
declare void @llvm.memset.p0i8.i32(i8* nocapture writeonly, i8, i32, i1 immarg) #1
If we want to let the aix as assembly compile pass without -u
it need to has following assembly code.
.extern .memset
(we do not output extern linkage for llvm instrinsic function.
even if we output the extern linkage for llvm intrinsic function, we should not out .extern llvm.memset.p0i8.i32,
instead of we should emit .extern memset)
for other llvm buildin function floatdidf . even if we do not call these function floatdidf in the c source code(the generated IR also do not the call __floatdidf . the function call
was generated in the LLVM optimized.
the function is not in the functions list of Module, but we still need to emit extern .__floatdidf
The solution for it as :
We record all the lllvm intrinsic extern symbol when transformCallee(), and emit all these symbol in the AsmPrinter::doFinalization(Module &M)
Reviewers: jasonliu, Sean Fertile, hubert.reinterpretcast,
Differential Revision: https://reviews.llvm.org/D78929
Without this change, names start with 'L' will get created as
temporary symbol in MCContext::createSymbol.
Some other potential prefix considered:
.L, does not work for AIX, as a function start with L will end
up with .L as prefix for its function entry point.
..L could work, but it does not play well with the convention
on AIX that anything start with '.' are considered as entry point.
L. could work, but not sure if it's safe enough, as it's possible
to have suffixes like .something append to a plain L, giving L.something
which is not necessarily a temporary.
That's why we picked L.. for now.
Differential Revision: https://reviews.llvm.org/D80831
Implement passing of ByVal formal arguments when the argument is passed
partly in the argument registers, with the remainder of the argument
passed on the stack.
Differential Revision: https://reviews.llvm.org/D78515
Adds support for passing a ByVal formal argument completely on the stack
(ie after all argument registers are exhausted).
Differential Revision: https://reviews.llvm.org/D78263
Kai Luo