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author | Andrew Trick <atrick@apple.com> | 2013-04-02 01:58:47 +0000 |
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committer | Andrew Trick <atrick@apple.com> | 2013-04-02 01:58:47 +0000 |
commit | e1d88cfb57f806fe87c4650379538ededa30dbc8 (patch) | |
tree | 8244096c62fcb40fe77e7cd536bb5e95ad3fb3bd /llvm/lib/Target | |
parent | 60bf5f45f799f77440b52deb3fe3ddec52e0ffa0 (diff) | |
download | bcm5719-llvm-e1d88cfb57f806fe87c4650379538ededa30dbc8.tar.gz bcm5719-llvm-e1d88cfb57f806fe87c4650379538ededa30dbc8.zip |
The divide unit is not pipeline, but it is still buffered.
Buffered means a later divide may be executed out-of-order while a
prior divide is sitting (buffered) in a reservation station.
You can tell it's not pipelined, because operations that use it
reserve it for more than one cycle:
def : WriteRes<WriteIDiv, [HWPort0, HWDivider]> {
let Latency = 25;
let ResourceCycles = [1, 10];
}
We don't currently distinguish between an unpipeline operation and one
that is split into multiple micro-ops requiring the same unit. Except
that the later may have NumMicroOps > 1 if they also consume
issue/dispatch resources.
llvm-svn: 178519
Diffstat (limited to 'llvm/lib/Target')
-rw-r--r-- | llvm/lib/Target/X86/X86SchedHaswell.td | 4 | ||||
-rw-r--r-- | llvm/lib/Target/X86/X86SchedSandyBridge.td | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/llvm/lib/Target/X86/X86SchedHaswell.td b/llvm/lib/Target/X86/X86SchedHaswell.td index b3eb460d3c3..7de6791f2e4 100644 --- a/llvm/lib/Target/X86/X86SchedHaswell.td +++ b/llvm/lib/Target/X86/X86SchedHaswell.td @@ -50,8 +50,8 @@ def HWPort15 : ProcResGroup<[HWPort1, HWPort5]>; def HWPort015 : ProcResGroup<[HWPort0, HWPort1, HWPort5]>; def HWPort0156: ProcResGroup<[HWPort0, HWPort1, HWPort5, HWPort6]>; -// Integer division issued on port 0, but uses the non-pipelined divider. -def HWDivider : ProcResource<1> { let Buffered = 0; } +// Integer division issued on port 0. +def HWDivider : ProcResource<1>; // Loads are 4 cycles, so ReadAfterLd registers needn't be available until 4 // cycles after the memory operand. diff --git a/llvm/lib/Target/X86/X86SchedSandyBridge.td b/llvm/lib/Target/X86/X86SchedSandyBridge.td index 66d78e4fc42..74d5f1b6eba 100644 --- a/llvm/lib/Target/X86/X86SchedSandyBridge.td +++ b/llvm/lib/Target/X86/X86SchedSandyBridge.td @@ -46,8 +46,8 @@ def SBPort05 : ProcResGroup<[SBPort0, SBPort5]>; def SBPort15 : ProcResGroup<[SBPort1, SBPort5]>; def SBPort015 : ProcResGroup<[SBPort0, SBPort1, SBPort5]>; -// Integer division issued on port 0, but uses the non-pipelined divider. -def SBDivider : ProcResource<1> { let Buffered = 0; } +// Integer division issued on port 0. +def SBDivider : ProcResource<1>; // Loads are 4 cycles, so ReadAfterLd registers needn't be available until 4 // cycles after the memory operand. |