diff --git a/clang/lib/Basic/Targets/PPC.h b/clang/lib/Basic/Targets/PPC.h
index 597508207ffbf..ad754462370f5 100644
--- a/clang/lib/Basic/Targets/PPC.h
+++ b/clang/lib/Basic/Targets/PPC.h
@@ -370,7 +370,6 @@ class LLVM_LIBRARY_VISIBILITY PPC32TargetInfo : public PPCTargetInfo {
       SizeType = UnsignedLong;
       PtrDiffType = SignedLong;
       IntPtrType = SignedLong;
-      SuitableAlign = 64;
       LongDoubleWidth = 64;
       LongDoubleAlign = DoubleAlign = 32;
       LongDoubleFormat = &llvm::APFloat::IEEEdouble();
@@ -409,7 +408,6 @@ class LLVM_LIBRARY_VISIBILITY PPC64TargetInfo : public PPCTargetInfo {
     if (Triple.isOSAIX()) {
       // TODO: Set appropriate ABI for AIX platform.
       DataLayout = "E-m:a-i64:64-n32:64";
-      SuitableAlign = 64;
       LongDoubleWidth = 64;
       LongDoubleAlign = DoubleAlign = 32;
       LongDoubleFormat = &llvm::APFloat::IEEEdouble();
diff --git a/clang/test/CodeGen/aix_alloca_align.c b/clang/test/CodeGen/aix_alloca_align.c
new file mode 100644
index 0000000000000..e235abdd16309
--- /dev/null
+++ b/clang/test/CodeGen/aix_alloca_align.c
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -triple=powerpc-ibm-aix-xcoff -S -emit-llvm < %s | \
+// RUN:   FileCheck --check-prefix=32BIT %s
+
+// RUN: %clang_cc1 -triple=powerpc64-ibm-aix-xcoff -S -emit-llvm < %s | \
+// RUN:   FileCheck --check-prefix=64BIT %s
+
+typedef __SIZE_TYPE__ size_t;
+extern void *alloca(size_t __size) __attribute__((__nothrow__));
+
+void foo() {
+  char *ptr1 = (char *)alloca(sizeof(char) * 9);
+  char *ptr2 = (char *)alloca(sizeof(char) * 32);
+}
+
+// 32BIT: %0 = alloca i8, i32 9, align 16
+// 32BIT: %1 = alloca i8, i32 32, align 16
+
+// 64BIT: %0 = alloca i8, i64 9, align 16
+// 64BIT: %1 = alloca i8, i64 32, align 16
diff --git a/clang/test/Preprocessor/init-ppc.c b/clang/test/Preprocessor/init-ppc.c
index 275757631c6c6..aa0f8c97de126 100644
--- a/clang/test/Preprocessor/init-ppc.c
+++ b/clang/test/Preprocessor/init-ppc.c
@@ -398,7 +398,7 @@
 // PPC-AIX:#define _LONG_LONG 1
 // PPC-AIX-NOT:#define _LP64 1
 // PPC-AIX:#define _POWER 1
-// PPC-AIX:#define __BIGGEST_ALIGNMENT__ 8
+// PPC-AIX:#define __BIGGEST_ALIGNMENT__ 16
 // PPC-AIX:#define __BIG_ENDIAN__ 1
 // PPC-AIX:#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
 // PPC-AIX:#define __CHAR16_TYPE__ unsigned short
diff --git a/clang/test/Preprocessor/init-ppc64.c b/clang/test/Preprocessor/init-ppc64.c
index b553d07183ec3..dd965b86b879f 100644
--- a/clang/test/Preprocessor/init-ppc64.c
+++ b/clang/test/Preprocessor/init-ppc64.c
@@ -666,7 +666,7 @@
 // PPC64-AIX:#define _LP64 1
 // PPC64-AIX:#define _POWER 1
 // PPC64-AIX:#define __64BIT__ 1
-// PPC64-AIX:#define __BIGGEST_ALIGNMENT__ 8
+// PPC64-AIX:#define __BIGGEST_ALIGNMENT__ 16
 // PPC64-AIX:#define __BIG_ENDIAN__ 1
 // PPC64-AIX:#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
 // PPC64-AIX:#define __CHAR16_TYPE__ unsigned short