Support very basic (doesn't include ABI support in the front-end, varags, ...) 256-bit argument passing and return for AVX

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110394 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 30 insertions, 4 deletions

diff --git a/lib/Target/X86/X86CallingConv.td b/lib/Target/X86/X86CallingConv.td
index a6a1e4e573..e3409effc3 100644
--- a/lib/Target/X86/X86CallingConv.td
+++ b/lib/Target/X86/X86CallingConv.td
@@ -33,13 +33,19 @@ def RetCC_X86Common : CallingConv<[
   CCIfType<[i16], CCAssignToReg<[AX, DX]>>,
   CCIfType<[i32], CCAssignToReg<[EAX, EDX]>>,
   CCIfType<[i64], CCAssignToReg<[RAX, RDX]>>,
-  
-  // Vector types are returned in XMM0 and XMM1, when they fit.  XMMM2 and XMM3
+
+  // 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
   // registers, it won't have vector types.
   CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
             CCAssignToReg<[XMM0,XMM1,XMM2,XMM3]>>,
 
+  // 256-bit vectors are returned in YMM0 and XMM1, when they fit. YMM2 and YMM3
+  // can only be used by ABI non-compliant code. This vector type is only
+  // supported while using the AVX target feature.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+            CCIfSubtarget<"hasAVX()", CCAssignToReg<[YMM0,YMM1,YMM2,YMM3]>>>,
+
   // MMX vector types are always returned in MM0. If the target doesn't have
   // MM0, it doesn't support these vector types.
   CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToReg<[MM0]>>,
@@ -164,11 +170,16 @@ def CC_X86_64_C : CallingConv<[
   CCIfType<[f32, f64, v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
             CCIfSubtarget<"hasSSE1()",
             CCAssignToReg<[XMM0, XMM1, XMM2, XMM3, XMM4, XMM5, XMM6, XMM7]>>>,
- 
+
+  // The first 8 256-bit vector arguments are passed in YMM registers.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+            CCIfSubtarget<"hasAVX()",
+            CCAssignToReg<[YMM0, YMM1, YMM2, YMM3, YMM4, YMM5, YMM6, YMM7]>>>,
+
   // Integer/FP values get stored in stack slots that are 8 bytes in size and
   // 8-byte aligned if there are no more registers to hold them.
   CCIfType<[i32, i64, f32, f64], CCAssignToStack<8, 8>>,
-  
+
   // Long doubles get stack slots whose size and alignment depends on the
   // subtarget.
   CCIfType<[f80], CCAssignToStack<0, 0>>,
@@ -176,6 +187,10 @@ def CC_X86_64_C : CallingConv<[
   // Vectors get 16-byte stack slots that are 16-byte aligned.
   CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
 
+  // 256-bit vectors get 32-byte stack slots that are 32-byte aligned.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+           CCAssignToStack<32, 32>>,
+
   // __m64 vectors get 8-byte stack slots that are 8-byte aligned.
   CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 8>>
 ]>;
@@ -271,9 +286,18 @@ def CC_X86_32_Common : CallingConv<[
   CCIfNotVarArg<CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64],
                 CCAssignToReg<[XMM0, XMM1, XMM2, XMM3]>>>,
 
+  // The first 4 AVX 256-bit vector arguments are passed in YMM registers.
+  CCIfNotVarArg<CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+                CCIfSubtarget<"hasAVX()",
+                CCAssignToReg<[YMM0, YMM1, YMM2, YMM3]>>>>,
+
   // Other SSE vectors get 16-byte stack slots that are 16-byte aligned.
   CCIfType<[v16i8, v8i16, v4i32, v2i64, v4f32, v2f64], CCAssignToStack<16, 16>>,
 
+  // 256-bit AVX vectors get 32-byte stack slots that are 32-byte aligned.
+  CCIfType<[v32i8, v16i16, v8i32, v4i64, v8f32, v4f64],
+           CCAssignToStack<32, 32>>,
+
   // __m64 vectors get 8-byte stack slots that are 4-byte aligned. They are
   // passed in the parameter area.
   CCIfType<[v8i8, v4i16, v2i32, v1i64], CCAssignToStack<8, 4>>]>;
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 44c95b5a6f..1b3d3e8b7a 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1633,6 +1633,8 @@ X86TargetLowering::LowerFormalArguments(SDValue Chain,
         RC = X86::FR32RegisterClass;
       else if (RegVT == MVT::f64)
         RC = X86::FR64RegisterClass;
+      else if (RegVT.isVector() && RegVT.getSizeInBits() == 256)
+        RC = X86::VR256RegisterClass;
       else if (RegVT.isVector() && RegVT.getSizeInBits() == 128)
         RC = X86::VR128RegisterClass;
       else if (RegVT.isVector() && RegVT.getSizeInBits() == 64)