[llvm-commits] [llvm] r157698 - in /llvm/trunk: lib/Target/X86/X86CallingConv.td test/CodeGen/X86/pass-four.ll

[Chris Lattner]

Author: lattner
Date: Wed May 30 12:50:14 2012
New Revision: 157698

URL: http://llvm.org/viewvc/llvm-project?rev=157698&view=rev
Log:
Extend the (abi-irrelevant) return convention to be able to return more than two values in
integer registers.  This is already supported by the fastcc convention, but it doesn't
hurt to support it in the standard conventions as well.

In cases where we can cheat at the calling convention, this allows us to avoid returning
things through memory in more cases.


Added:
    llvm/trunk/test/CodeGen/X86/pass-four.ll
Modified:
    llvm/trunk/lib/Target/X86/X86CallingConv.td

Modified: llvm/trunk/lib/Target/X86/X86CallingConv.td
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86CallingConv.td?rev=157698&r1=157697&r2=157698&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86CallingConv.td (original)
+++ llvm/trunk/lib/Target/X86/X86CallingConv.td Wed May 30 12:50:14 2012
@@ -29,10 +29,13 @@
   // up in AX and AH, which overlap. Front-ends wishing to conform to the ABI
   // for functions that return two i8 values are currently expected to pack the
   // values into an i16 (which uses AX, and thus AL:AH).
-  CCIfType<[i8] , CCAssignToReg<[AL, DL]>>,
-  CCIfType<[i16], CCAssignToReg<[AX, DX]>>,
-  CCIfType<[i32], CCAssignToReg<[EAX, EDX]>>,
-  CCIfType<[i64], CCAssignToReg<[RAX, RDX]>>,
+  //
+  // For code that doesn't care about the ABI, we allow returning more than two
+  // integer values in registers.
+  CCIfType<[i8] , CCAssignToReg<[AL, DL, CL]>>,
+  CCIfType<[i16], CCAssignToReg<[AX, DX, CX]>>,
+  CCIfType<[i32], CCAssignToReg<[EAX, EDX, ECX]>>,
+  CCIfType<[i64], CCAssignToReg<[RAX, RDX, RCX, R11]>>,
 
   // Vector types are returned in XMM0 and XMM1, when they fit.  XMM2 and XMM3
   // can only be used by ABI non-compliant code. If the target doesn't have XMM

Added: llvm/trunk/test/CodeGen/X86/pass-four.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/pass-four.ll?rev=157698&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/pass-four.ll (added)
+++ llvm/trunk/test/CodeGen/X86/pass-four.ll Wed May 30 12:50:14 2012
@@ -0,0 +1,17 @@
+; RUN: llc < %s | FileCheck %s
+target datalayout = "e-p:64:64:64-S128-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f16:16:16-f32:32:32-f64:64:64-f128:128:128-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
+target triple = "x86_64-apple-darwin11.3.0"
+
+
+define { i8*, i64, i64*, i64 } @copy_4(i8* %a, i64 %b, i64* %c, i64 %d) nounwind {
+entry:
+  %0 = insertvalue { i8*, i64, i64*, i64 } undef, i8* %a, 0
+  %1 = insertvalue { i8*, i64, i64*, i64 } %0, i64 %b, 1
+  %2 = insertvalue { i8*, i64, i64*, i64 } %1, i64* %c, 2
+  %3 = insertvalue { i8*, i64, i64*, i64 } %2, i64 %d, 3
+  ret { i8*, i64, i64*, i64 } %3
+}
+
+; CHECK: copy_4:
+; CHECK-NOT: (%rdi)
+; CHECK: ret