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| author | David Majnemer <david.majnemer@gmail.com> | 2015-02-23 21:50:30 +0000 |
|---|---|---|
| committer | David Majnemer <david.majnemer@gmail.com> | 2015-02-23 21:50:30 +0000 |
| commit | 006c490ba8e26c3f34ea8efc34ad0e983d5e3107 (patch) | |
| tree | 0dadb5637310440e71501626d6fc105fe273f036 /llvm/lib/Analysis/CostModel.cpp | |
| parent | 31d868b6189a48e9ee398b15d91ccc1ec53f2b83 (diff) | |
| download | bcm5719-llvm-006c490ba8e26c3f34ea8efc34ad0e983d5e3107.tar.gz bcm5719-llvm-006c490ba8e26c3f34ea8efc34ad0e983d5e3107.zip | |
X86: Use a smaller 'mov' instruction for stack probe calls
Prologue emission, in some cases, requires calls to a stack probe helper
function. The amount of stack to probe is passed as a register
argument in the Win64 ABI but the instruction sequence used is
pessimistic: it assumes that the number of bytes to probe is greater
than 4 GB.
Instead, select a more appropriate opcode depending on the number of
bytes we are going to probe.
llvm-svn: 230270
Diffstat (limited to 'llvm/lib/Analysis/CostModel.cpp')
0 files changed, 0 insertions, 0 deletions
