[llvm-branch-commits] [llvm-branch] r104762 - in /llvm/branches/Apple/whitney: lib/Target/X86/AsmParser/X86AsmParser.cpp test/MC/AsmParser/X86/x86_32-new-encoder.s

[Daniel Dunbar]

Author: ddunbar
Date: Wed May 26 17:28:43 2010
New Revision: 104762

URL: http://llvm.org/viewvc/llvm-project?rev=104762&view=rev
Log:
Changed the encoding of X86 floating point stack operations where both operands are st(0). These can be encoded using an opcode for storing in st(0) or using an opcode for storing in st(i), where i can also be 0. To allow testing with the darwin assembler and get a matching binary the opcode for storing in st(0) is now used. To do this the same logical trick is use from the darwin assembler in converting things like this:

fmul %st(0), %st

into this:

fmul %st(0)

by looking for the second operand being X86::ST0 for specific floating point
mnemonics then removing the second X86::ST0 operand.  This also has the add
benefit to allow things like:

fmul %st(1), %st

that llvm-mc did not assemble.

Modified:
    llvm/branches/Apple/whitney/lib/Target/X86/AsmParser/X86AsmParser.cpp
    llvm/branches/Apple/whitney/test/MC/AsmParser/X86/x86_32-new-encoder.s

Modified: llvm/branches/Apple/whitney/lib/Target/X86/AsmParser/X86AsmParser.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/whitney/lib/Target/X86/AsmParser/X86AsmParser.cpp?rev=104762&r1=104761&r2=104762&view=diff
==============================================================================
--- llvm/branches/Apple/whitney/lib/Target/X86/AsmParser/X86AsmParser.cpp (original)
+++ llvm/branches/Apple/whitney/lib/Target/X86/AsmParser/X86AsmParser.cpp Wed May 26 17:28:43 2010
@@ -706,6 +706,17 @@
     Operands.erase(Operands.begin() + 1);
   }
 
+  // FIXME: Hack to handle "f{mul*,add*,sub*,div*} $op, st(0)" the same as
+  // "f{mul*,add*,sub*,div*} $op"
+  if ((Name.startswith("fmul") || Name.startswith("fadd") ||
+       Name.startswith("fsub") || Name.startswith("fdiv")) &&
+      Operands.size() == 3 &&
+      static_cast<X86Operand*>(Operands[2])->isReg() &&
+      static_cast<X86Operand*>(Operands[2])->getReg() == X86::ST0) {
+    delete Operands[2];
+    Operands.erase(Operands.begin() + 2);
+  }
+
   return false;
 }
 

Modified: llvm/branches/Apple/whitney/test/MC/AsmParser/X86/x86_32-new-encoder.s
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/whitney/test/MC/AsmParser/X86/x86_32-new-encoder.s?rev=104762&r1=104761&r2=104762&view=diff
==============================================================================
--- llvm/branches/Apple/whitney/test/MC/AsmParser/X86/x86_32-new-encoder.s (original)
+++ llvm/branches/Apple/whitney/test/MC/AsmParser/X86/x86_32-new-encoder.s Wed May 26 17:28:43 2010
@@ -277,3 +277,28 @@
 // CHECK: cmpsd $7, %xmm0, %xmm1
 // CHECK: encoding: [0xf2,0x0f,0xc2,0xc8,0x07]
         cmpordsd %xmm0, %xmm1
+
+// rdar://7995856
+// CHECK: fmul	%st(0)
+// CHECK:  encoding: [0xd8,0xc8]
+        fmul %st(0), %st
+
+// CHECK: fadd	%st(0)
+// CHECK:  encoding: [0xd8,0xc0]
+        fadd %st(0), %st
+
+// CHECK: fsub	%st(0)
+// CHECK:  encoding: [0xd8,0xe0]
+        fsub %st(0), %st
+
+// CHECK: fsubr	%st(0)
+// CHECK:  encoding: [0xd8,0xe8]
+        fsubr %st(0), %st
+
+// CHECK: fdivr	%st(0)
+// CHECK:  encoding: [0xd8,0xf8]
+        fdivr %st(0), %st
+
+// CHECK: fdiv	%st(0)
+// CHECK:  encoding: [0xd8,0xf0]
+        fdiv %st(0), %st