llvm-6502/test/CodeGen/ARM/2012-10-04-AAPCS-byval-align8.ll

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; RUN: llc < %s -mtriple=armv7-none-linux-gnueabi | FileCheck %s
; Test that we correctly use registers and align elements when using va_arg
%struct_t = type { double, double, double }
@static_val = constant %struct_t { double 1.0, double 2.0, double 3.0 }
declare void @llvm.va_start(i8*) nounwind
declare void @llvm.va_end(i8*) nounwind
; CHECK-LABEL: test_byval_8_bytes_alignment:
define void @test_byval_8_bytes_alignment(i32 %i, ...) {
entry:
; CHECK: sub sp, sp, #12
; CHECK: sub sp, sp, #4
; CHECK: stmib sp, {r1, r2, r3}
%g = alloca i8*
%g1 = bitcast i8** %g to i8*
call void @llvm.va_start(i8* %g1)
; CHECK: add [[REG:(r[0-9]+)|(lr)]], {{(r[0-9]+)|(lr)}}, #7
; CHECK: bfc [[REG]], #0, #3
%0 = va_arg i8** %g, double
call void @llvm.va_end(i8* %g1)
ret void
}
; CHECK-LABEL: main:
; CHECK: movw [[BASE:r[0-9]+]], :lower16:static_val
; CHECK: movt [[BASE]], :upper16:static_val
; ldm is not formed when the coalescer failed to coalesce everything.
Allocate local registers in order for optimal coloring. Also avoid locals evicting locals just because they want a cheaper register. Problem: MI Sched knows exactly how many registers we have and assumes they can be colored. In cases where we have large blocks, usually from unrolled loops, greedy coloring fails. This is a source of "regressions" from the MI Scheduler on x86. I noticed this issue on x86 where we have long chains of two-address defs in the same live range. It's easy to see this in matrix multiplication benchmarks like IRSmk and even the unit test misched-matmul.ll. A fundamental difference between the LLVM register allocator and conventional graph coloring is that in our model a live range can't discover its neighbors, it can only verify its neighbors. That's why we initially went for greedy coloring and added eviction to deal with the hard cases. However, for singly defined and two-address live ranges, we can optimally color without visiting neighbors simply by processing the live ranges in instruction order. Other beneficial side effects: It is much easier to understand and debug regalloc for large blocks when the live ranges are allocated in order. Yes, global allocation is still very confusing, but it's nice to be able to comprehend what happened locally. Heuristics could be added to bias register assignment based on instruction locality (think late register pairing, banks...). Intuituvely this will make some test cases that are on the threshold of register pressure more stable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187139 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-25 18:35:14 +00:00
; CHECK: ldrd r2, [[TMP:r[0-9]+]], {{\[}}[[BASE]]{{\]}}
; CHECK: movw r0, #555
define i32 @main() {
entry:
call void (i32, ...)* @test_byval_8_bytes_alignment(i32 555, %struct_t* byval @static_val)
ret i32 0
}
declare void @f(double);
; CHECK-LABEL: test_byval_8_bytes_alignment_fixed_arg:
; CHECK-NOT: str r1
; CHECK: str r3, [sp, #12]
; CHECK: str r2, [sp, #8]
; CHECK-NOT: str r1
define void @test_byval_8_bytes_alignment_fixed_arg(i32 %n1, %struct_t* byval %val) nounwind {
entry:
[opaque pointer type] Add textual IR support for explicit type parameter to getelementptr instruction One of several parallel first steps to remove the target type of pointers, replacing them with a single opaque pointer type. This adds an explicit type parameter to the gep instruction so that when the first parameter becomes an opaque pointer type, the type to gep through is still available to the instructions. * This doesn't modify gep operators, only instructions (operators will be handled separately) * Textual IR changes only. Bitcode (including upgrade) and changing the in-memory representation will be in separate changes. * geps of vectors are transformed as: getelementptr <4 x float*> %x, ... ->getelementptr float, <4 x float*> %x, ... Then, once the opaque pointer type is introduced, this will ultimately look like: getelementptr float, <4 x ptr> %x with the unambiguous interpretation that it is a vector of pointers to float. * address spaces remain on the pointer, not the type: getelementptr float addrspace(1)* %x ->getelementptr float, float addrspace(1)* %x Then, eventually: getelementptr float, ptr addrspace(1) %x Importantly, the massive amount of test case churn has been automated by same crappy python code. I had to manually update a few test cases that wouldn't fit the script's model (r228970,r229196,r229197,r229198). The python script just massages stdin and writes the result to stdout, I then wrapped that in a shell script to handle replacing files, then using the usual find+xargs to migrate all the files. update.py: import fileinput import sys import re ibrep = re.compile(r"(^.*?[^%\w]getelementptr inbounds )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))") normrep = re.compile( r"(^.*?[^%\w]getelementptr )(((?:<\d* x )?)(.*?)(| addrspace\(\d\)) *\*(|>)(?:$| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$))") def conv(match, line): if not match: return line line = match.groups()[0] if len(match.groups()[5]) == 0: line += match.groups()[2] line += match.groups()[3] line += ", " line += match.groups()[1] line += "\n" return line for line in sys.stdin: if line.find("getelementptr ") == line.find("getelementptr inbounds"): if line.find("getelementptr inbounds") != line.find("getelementptr inbounds ("): line = conv(re.match(ibrep, line), line) elif line.find("getelementptr ") != line.find("getelementptr ("): line = conv(re.match(normrep, line), line) sys.stdout.write(line) apply.sh: for name in "$@" do python3 `dirname "$0"`/update.py < "$name" > "$name.tmp" && mv "$name.tmp" "$name" rm -f "$name.tmp" done The actual commands: From llvm/src: find test/ -name *.ll | xargs ./apply.sh From llvm/src/tools/clang: find test/ -name *.mm -o -name *.m -o -name *.cpp -o -name *.c | xargs -I '{}' ../../apply.sh "{}" From llvm/src/tools/polly: find test/ -name *.ll | xargs ./apply.sh After that, check-all (with llvm, clang, clang-tools-extra, lld, compiler-rt, and polly all checked out). The extra 'rm' in the apply.sh script is due to a few files in clang's test suite using interesting unicode stuff that my python script was throwing exceptions on. None of those files needed to be migrated, so it seemed sufficient to ignore those cases. Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7636 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230786 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-27 19:29:02 +00:00
%a = getelementptr inbounds %struct_t, %struct_t* %val, i32 0, i32 0
%0 = load double, double* %a
call void (double)* @f(double %0)
ret void
}
; CHECK-LABEL: main_fixed_arg:
; CHECK: movw [[BASE:r[0-9]+]], :lower16:static_val
; CHECK: movt [[BASE]], :upper16:static_val
; ldm is not formed when the coalescer failed to coalesce everything.
Allocate local registers in order for optimal coloring. Also avoid locals evicting locals just because they want a cheaper register. Problem: MI Sched knows exactly how many registers we have and assumes they can be colored. In cases where we have large blocks, usually from unrolled loops, greedy coloring fails. This is a source of "regressions" from the MI Scheduler on x86. I noticed this issue on x86 where we have long chains of two-address defs in the same live range. It's easy to see this in matrix multiplication benchmarks like IRSmk and even the unit test misched-matmul.ll. A fundamental difference between the LLVM register allocator and conventional graph coloring is that in our model a live range can't discover its neighbors, it can only verify its neighbors. That's why we initially went for greedy coloring and added eviction to deal with the hard cases. However, for singly defined and two-address live ranges, we can optimally color without visiting neighbors simply by processing the live ranges in instruction order. Other beneficial side effects: It is much easier to understand and debug regalloc for large blocks when the live ranges are allocated in order. Yes, global allocation is still very confusing, but it's nice to be able to comprehend what happened locally. Heuristics could be added to bias register assignment based on instruction locality (think late register pairing, banks...). Intuituvely this will make some test cases that are on the threshold of register pressure more stable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187139 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-25 18:35:14 +00:00
; CHECK: ldrd r2, [[TMP:r[0-9]+]], {{\[}}[[BASE]]{{\]}}
; CHECK: movw r0, #555
define i32 @main_fixed_arg() {
entry:
call void (i32, %struct_t*)* @test_byval_8_bytes_alignment_fixed_arg(i32 555, %struct_t* byval @static_val)
ret i32 0
}