[llvm-commits] [llvm] r55190 - in /llvm/trunk/lib/Target/X86: X86Instr64bit.td X86InstrInfo.td

Dan Gohman gohman at apple.com
Fri Aug 22 12:19:32 PDT 2008


Author: djg
Date: Fri Aug 22 14:19:31 2008
New Revision: 55190

URL: http://llvm.org/viewvc/llvm-project?rev=55190&view=rev
Log:
Anyext tweaks for x86. When extloading a value to i32 or i64, choose
instructions that define the full 32 or 64-bit value. When anyexting
from i8 to i16 or i32, it's not necessary to zero out the high
portion of the register.

Modified:
    llvm/trunk/lib/Target/X86/X86Instr64bit.td
    llvm/trunk/lib/Target/X86/X86InstrInfo.td

Modified: llvm/trunk/lib/Target/X86/X86Instr64bit.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86Instr64bit.td?rev=55190&r1=55189&r2=55190&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86Instr64bit.td (original)
+++ llvm/trunk/lib/Target/X86/X86Instr64bit.td Fri Aug 22 14:19:31 2008
@@ -1254,15 +1254,9 @@
 def : Pat<(zextloadi64i1 addr:$src), (MOVZX64rm8 addr:$src)>;
 
 // extload
-def : Pat<(extloadi64i1 addr:$src),
-          (INSERT_SUBREG (i64 (IMPLICIT_DEF)), (MOV8rm addr:$src),
-                         x86_subreg_8bit)>;
-def : Pat<(extloadi64i8 addr:$src),
-          (INSERT_SUBREG (i64 (IMPLICIT_DEF)), (MOV8rm addr:$src),
-                         x86_subreg_8bit)>;
-def : Pat<(extloadi64i16 addr:$src),
-          (INSERT_SUBREG (i64 (IMPLICIT_DEF)), (MOV16rm addr:$src),
-                         x86_subreg_16bit)>;
+def : Pat<(extloadi64i1 addr:$src),  (MOVZX64rm8  addr:$src)>;
+def : Pat<(extloadi64i8 addr:$src),  (MOVZX64rm8  addr:$src)>;
+def : Pat<(extloadi64i16 addr:$src), (MOVZX64rm16 addr:$src)>;
 def : Pat<(extloadi64i32 addr:$src),
           (INSERT_SUBREG (i64 (IMPLICIT_DEF)), (MOV32rm addr:$src),
                          x86_subreg_32bit)>;

Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.td?rev=55190&r1=55189&r2=55190&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.td (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.td Fri Aug 22 14:19:31 2008
@@ -2784,19 +2784,24 @@
 
 // extload bool -> extload byte
 def : Pat<(extloadi8i1 addr:$src),   (MOV8rm      addr:$src)>;
-def : Pat<(extloadi16i1 addr:$src),  (MOVZX16rm8  addr:$src)>,
-         Requires<[In32BitMode]>;
+def : Pat<(extloadi16i1 addr:$src),
+          (INSERT_SUBREG (i16 (IMPLICIT_DEF)), (MOV8rm addr:$src),
+                         x86_subreg_8bit)>;
+def : Pat<(extloadi16i8 addr:$src),
+          (INSERT_SUBREG (i16 (IMPLICIT_DEF)), (MOV8rm addr:$src),
+                         x86_subreg_8bit)>;
+// For extloads with 32-bit results, chose instructions that
+// define the whole 32 bits of the result, to avoid partial-register
+// updates.
 def : Pat<(extloadi32i1 addr:$src),  (MOVZX32rm8  addr:$src)>;
-def : Pat<(extloadi16i8 addr:$src),  (MOVZX16rm8  addr:$src)>,
-         Requires<[In32BitMode]>;
 def : Pat<(extloadi32i8 addr:$src),  (MOVZX32rm8  addr:$src)>;
 def : Pat<(extloadi32i16 addr:$src), (MOVZX32rm16 addr:$src)>;
 
 // anyext
-def : Pat<(i16 (anyext GR8 :$src)), (MOVZX16rr8  GR8 :$src)>,
-         Requires<[In32BitMode]>;
-def : Pat<(i32 (anyext GR8 :$src)), (MOVZX32rr8  GR8 :$src)>,
-         Requires<[In32BitMode]>;
+def : Pat<(i16 (anyext GR8:$src)),
+          (INSERT_SUBREG (i16 (IMPLICIT_DEF)), GR8:$src, x86_subreg_8bit)>;
+def : Pat<(i32 (anyext GR8:$src)),
+          (INSERT_SUBREG (i32 (IMPLICIT_DEF)), GR8:$src, x86_subreg_8bit)>;
 def : Pat<(i32 (anyext GR16:$src)),
           (INSERT_SUBREG (i32 (IMPLICIT_DEF)), GR16:$src, x86_subreg_16bit)>;
 





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