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| author | Dan Gohman <gohman@apple.com> | 2008-10-17 01:33:43 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2008-10-17 01:33:43 +0000 |
| commit | ca0546facc5af4c27a5efd5ff80935ba05ae030a (patch) | |
| tree | e41965726caebfa000f4fefdfc491d4ad93cb745 /llvm/test/TableGen | |
| parent | a39b0a1f05337718973fb9a52df61b302e766109 (diff) | |
| download | bcm5719-llvm-ca0546facc5af4c27a5efd5ff80935ba05ae030a.tar.gz bcm5719-llvm-ca0546facc5af4c27a5efd5ff80935ba05ae030a.zip | |
Fun x86 encoding tricks: when adding an immediate value of 128,
use a SUB instruction instead of an ADD, because -128 can be
encoded in an 8-bit signed immediate field, while +128 can't be.
This avoids the need for a 32-bit immediate field in this case.
A similar optimization applies to 64-bit adds with 0x80000000,
with the 32-bit signed immediate field.
To support this, teach tablegen how to handle 64-bit constants.
llvm-svn: 57663
Diffstat (limited to 'llvm/test/TableGen')
| -rw-r--r-- | llvm/test/TableGen/2006-09-18-LargeInt.td | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/llvm/test/TableGen/2006-09-18-LargeInt.td b/llvm/test/TableGen/2006-09-18-LargeInt.td index 0e441c5b477..afd813fab65 100644 --- a/llvm/test/TableGen/2006-09-18-LargeInt.td +++ b/llvm/test/TableGen/2006-09-18-LargeInt.td @@ -1,4 +1,4 @@ -// RUN: tblgen %s | grep -- -65536 +// RUN: tblgen %s | grep -- 4294901760 def X { int Y = 0xFFFF0000; |
