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* X86: Do not use llc -march in tests.Matthias Braun2017-08-021-1/+1
| | | | | | | | | | | | | | | `llc -march` is problematic because it only switches the target architecture, but leaves the operating system unchanged. This occasionally leads to indeterministic tests because the OS from LLVM_DEFAULT_TARGET_TRIPLE is used. However we can simply always use `llc -mtriple` instead. This changes all the tests to do this to avoid people using -march when they copy and paste parts of tests. See also the discussion in https://reviews.llvm.org/D35287 llvm-svn: 309774
* [opaque pointer type] Add textual IR support for explicit type parameter to ↵David Blaikie2015-02-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | load instruction Essentially the same as the GEP change in r230786. A similar migration script can be used to update test cases, though a few more test case improvements/changes were required this time around: (r229269-r229278) import fileinput import sys import re pat = re.compile(r"((?:=|:|^)\s*load (?:atomic )?(?:volatile )?(.*?))(| addrspace\(\d+\) *)\*($| *(?:%|@|null|undef|blockaddress|getelementptr|addrspacecast|bitcast|inttoptr|\[\[[a-zA-Z]|\{\{).*$)") for line in sys.stdin: sys.stdout.write(re.sub(pat, r"\1, \2\3*\4", line)) Reviewers: rafael, dexonsmith, grosser Differential Revision: http://reviews.llvm.org/D7649 llvm-svn: 230794
* [RegAlloc] Make tryInstructionSplit less aggressive.Quentin Colombet2014-01-021-0/+33
The greedy register allocator tries to split a live-range around each instruction where it is used or defined to relax the constraints on the entire live-range (this is a last chance split before falling back to spill). The goal is to have a big live-range that is unconstrained (i.e., that can use the largest legal register class) and several small local live-range that carry the constraints implied by each instruction. E.g., Let csti be the constraints on operation i. V1= op1 V1(cst1) op2 V1(cst2) V1 live-range is constrained on the intersection of cst1 and cst2. tryInstructionSplit relaxes those constraints by aggressively splitting each def/use point: V1= V2 = V1 V3 = V2 op1 V3(cst1) V4 = V2 op2 V4(cst2) Because of how the coalescer infrastructure works, each new variable (V3, V4) that is alive at the same time as V1 (or its copy, here V2) interfere with V1. Thus, we end up with an uncoalescable copy for each split point. To make tryInstructionSplit less aggressive, we check if the split point actually relaxes the constraints on the whole live-range. If it does not, we do not insert it. Indeed, it will not help the global allocation problem: - V1 will have the same constraints. - V1 will have the same interference + possibly the newly added split variable VS. - VS will produce an uncoalesceable copy if alive at the same time as V1. <rdar://problem/15570057> llvm-svn: 198369
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