[cfe-commits] r167440 - in /cfe/trunk: lib/CodeGen/TargetInfo.cpp test/CodeGen/arm-arguments.c

Manman Ren mren at apple.com
Mon Nov 5 20:58:01 PST 2012


Author: mren
Date: Mon Nov  5 22:58:01 2012
New Revision: 167440

URL: http://llvm.org/viewvc/llvm-project?rev=167440&view=rev
Log:
ARM byval: when type alignment is bigger than ABI alignment, instead of
disabling byval, we set realign to true.

It will perform an aligned alloca, and call memcpy to copy the byval
argument to the local variable.
Change the size threshold back to 64 bytes.

rdar://12596507

Modified:
    cfe/trunk/lib/CodeGen/TargetInfo.cpp
    cfe/trunk/test/CodeGen/arm-arguments.c

Modified: cfe/trunk/lib/CodeGen/TargetInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.cpp?rev=167440&r1=167439&r2=167440&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/TargetInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/TargetInfo.cpp Mon Nov  5 22:58:01 2012
@@ -3221,16 +3221,15 @@
 
   // Support byval for ARM.
   // The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at most 8-byte.
-  // Byval can't handle the case where type alignment is bigger than ABI alignment.
-  // We also increase the threshold for byval due to its overhead.
+  // We realign the indirect argument if type alignment is bigger than ABI alignment.
   uint64_t ABIAlign = 4;
   uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
   if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
       getABIKind() == ARMABIInfo::AAPCS)
     ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
-  if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64*8) &&
-      TyAlign <= ABIAlign) {
-    return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
+  if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
+    return ABIArgInfo::getIndirect(0, /*ByVal=*/true,
+           /*Realign=*/TyAlign <= ABIAlign ? false : true);
   }
 
   // Otherwise, pass by coercing to a structure of the appropriate size.

Modified: cfe/trunk/test/CodeGen/arm-arguments.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/arm-arguments.c?rev=167440&r1=167439&r2=167440&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/arm-arguments.c (original)
+++ cfe/trunk/test/CodeGen/arm-arguments.c Mon Nov  5 22:58:01 2012
@@ -191,3 +191,35 @@
 // AAPCS: %[[a:.*]] = alloca { [1 x i32] }
 // AAPCS: %[[gep:.*]] = getelementptr { [1 x i32] }* %[[a]], i32 0, i32 0
 // AAPCS: load [1 x i32]* %[[gep]]
+
+// rdar://12596507
+struct s35
+{
+   float v[18]; //make sure byval is on.
+} __attribute__((aligned(16)));
+typedef struct s35 s35_with_align;
+
+typedef __attribute__((neon_vector_type(4))) float float32x4_t;
+static __attribute__((__always_inline__, __nodebug__)) float32x4_t vaddq_f32(
+       float32x4_t __a, float32x4_t __b) {
+ return __a + __b;
+}
+float32x4_t f35(int i, s35_with_align s1, s35_with_align s2) {
+  float32x4_t v = vaddq_f32(*(float32x4_t *)&s1,
+                            *(float32x4_t *)&s2);
+  return v;
+}
+// APCS-GNU: define <4 x float> @f35(i32 %i, %struct.s35* byval, %struct.s35* byval)
+// APCS-GNU: %[[a:.*]] = alloca %struct.s35, align 16
+// APCS-GNU: %[[b:.*]] = bitcast %struct.s35* %[[a]] to i8*
+// APCS-GNU: %[[c:.*]] = bitcast %struct.s35* %0 to i8*
+// APCS-GNU: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %[[b]], i8* %[[c]]
+// APCS-GNU: %[[d:.*]] = bitcast %struct.s35* %[[a]] to <4 x float>*
+// APCS-GNU: load <4 x float>* %[[d]], align 16
+// AAPCS: define arm_aapcscc <4 x float> @f35(i32 %i, %struct.s35* byval, %struct.s35* byval)
+// AAPCS: %[[a:.*]] = alloca %struct.s35, align 16
+// AAPCS: %[[b:.*]] = bitcast %struct.s35* %[[a]] to i8*
+// AAPCS: %[[c:.*]] = bitcast %struct.s35* %0 to i8*
+// AAPCS: call void @llvm.memcpy.p0i8.p0i8.i32(i8* %[[b]], i8* %[[c]]
+// AAPCS: %[[d:.*]] = bitcast %struct.s35* %[[a]] to <4 x float>*
+// AAPCS: load <4 x float>* %[[d]], align 16





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