Add a -Z flag for LLVM align attributes on arguments #49122
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LLVM seems to still put the assume calls in when inlining, so this probably isn't in a place where it can be turned on by default, but it's interesting to experiment with. For example, this makes `swap::<u64x8>` be 8x `vmovaps ymm` instead of 16x `vmovups xmm`, on my cpu.
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r? @cramertj (rust_highfive has picked a reviewer for you, use r? to override) |
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@bors r+ |
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@scottmcm Can you create an issue tracking this flag? |
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Tracking issue added: #49185 (oops, don't know why what I typed before triggered the bot) |
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@scottmcm: 🔑 Insufficient privileges: Not in reviewers |
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@scottmcm: 🔑 Insufficient privileges: not in try users |
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Hmm, there's no bors comment ACKing the r+ here. Does it need to be done again since the bot was broken? |
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@bors r+ |
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📌 Commit b498192 has been approved by |
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alexcrichton
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Mar 23, 2018
Add a -Z flag for LLVM align attributes on arguments LLVM seems to still put the assume calls in when inlining, so this probably isn't in a place where it can be turned on by default, but it's interesting to experiment with. For example, this makes `mem::swap::<u64x8>` be 8x `vmovaps ymm` instead of 16x `vmovups xmm`, on my cpu.
kennytm
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Mar 24, 2018
Add a -Z flag for LLVM align attributes on arguments LLVM seems to still put the assume calls in when inlining, so this probably isn't in a place where it can be turned on by default, but it's interesting to experiment with. For example, this makes `mem::swap::<u64x8>` be 8x `vmovaps ymm` instead of 16x `vmovups xmm`, on my cpu.
kennytm
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Mar 24, 2018
Add a -Z flag for LLVM align attributes on arguments LLVM seems to still put the assume calls in when inlining, so this probably isn't in a place where it can be turned on by default, but it's interesting to experiment with. For example, this makes `mem::swap::<u64x8>` be 8x `vmovaps ymm` instead of 16x `vmovups xmm`, on my cpu.
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LLVM seems to still put the assume calls in when inlining, so this probably isn't in a place where it can be turned on by default, but it's interesting to experiment with.
For example, this makes
mem::swap::<u64x8>be 8xvmovaps ymminstead of 16xvmovups xmm, on my cpu.