diff options
| author | Chris Lattner <sabre@nondot.org> | 2009-07-11 23:17:29 +0000 |
|---|---|---|
| committer | Chris Lattner <sabre@nondot.org> | 2009-07-11 23:17:29 +0000 |
| commit | 65a7a6f7a3a9fc5fd2e50200c81a6ec00a78ffd3 (patch) | |
| tree | 68b2b18bc37741d05f80c7764b1094b747df8638 /lib | |
| parent | 14f7511f46ed61b0dbaaf566e1170f40b9663924 (diff) | |
fix x86-64 static codegen to materialize the address of a global with movl instead
of lea. It is better for code size (and presumably efficiency) to use:
movl $foo, %eax
rather than:
leal foo, eax
Both give a nice zero extending "move immediate" instruction, the former is just
smaller. Note that global addresses should be handled different by the x86
backend, but I chose to follow the style already in place and add more fixme's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75403 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/X86/X86Instr64bit.td | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/lib/Target/X86/X86Instr64bit.td b/lib/Target/X86/X86Instr64bit.td index 2fe26c0b70..ba886e45ac 100644 --- a/lib/Target/X86/X86Instr64bit.td +++ b/lib/Target/X86/X86Instr64bit.td @@ -45,9 +45,8 @@ def lea64_32mem : Operand<i32> { // Complex Pattern Definitions. // def lea64addr : ComplexPattern<i64, 4, "SelectLEAAddr", - [add, mul, X86mul_imm, shl, or, frameindex, X86Wrapper, - X86WrapperRIP], - []>; + [add, mul, X86mul_imm, shl, or, frameindex, + X86WrapperRIP], []>; def tls64addr : ComplexPattern<i64, 4, "SelectTLSADDRAddr", [tglobaltlsaddr], []>; @@ -1421,6 +1420,19 @@ def : Pat<(i64 (X86Wrapper tglobaladdr :$dst)), def : Pat<(i64 (X86Wrapper texternalsym:$dst)), (MOV64ri texternalsym:$dst)>, Requires<[NotSmallCode]>; +// In static codegen with small code model, we can get the address of a label +// into a register with 'movl'. FIXME: This is a hack, the 'imm' predicate of +// the MOV64ri64i32 should accept these. +def : Pat<(i64 (X86Wrapper tconstpool :$dst)), + (MOV64ri64i32 tconstpool :$dst)>, Requires<[SmallCode]>; +def : Pat<(i64 (X86Wrapper tjumptable :$dst)), + (MOV64ri64i32 tjumptable :$dst)>, Requires<[SmallCode]>; +def : Pat<(i64 (X86Wrapper tglobaladdr :$dst)), + (MOV64ri64i32 tglobaladdr :$dst)>, Requires<[SmallCode]>; +def : Pat<(i64 (X86Wrapper texternalsym:$dst)), + (MOV64ri64i32 texternalsym:$dst)>, Requires<[SmallCode]>; + + // If we have small model and -static mode, it is safe to store global addresses // directly as immediates. FIXME: This is really a hack, the 'imm' predicate // for MOV64mi32 should handle this sort of thing. |