[builtins] Fix c?zdi2 on sparc64/Linux and ignore riscv32
On sparc64/Linux, sparc64 isn't defined; the canonical way of
checking for sparc64 is sparc && arch64, which also works on the
BSDs and Solaris. Since this problem does not occur on 32-bit
architectures, riscv32 can be ignored. This fixes and refines rL324593.
Patch by jrtc27 (James Clarke)
Differential Revision: https://reviews.llvm.org/D43146
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@342504 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/builtins/clzdi2.c b/lib/builtins/clzdi2.c
index b56d98f..1819e6b 100644
--- a/lib/builtins/clzdi2.c
+++ b/lib/builtins/clzdi2.c
@@ -16,8 +16,13 @@
/* Returns: the number of leading 0-bits */
-#if !defined(__clang__) && (defined(__sparc64__) || defined(__mips64) || defined(__riscv__))
-/* gcc resolves __builtin_clz -> __clzdi2 leading to infinite recursion */
+#if !defined(__clang__) && \
+ ((defined(__sparc__) && defined(__arch64__)) || \
+ defined(__mips64) || \
+ (defined(__riscv) && __SIZEOF_POINTER__ >= 8))
+/* On 64-bit architectures with neither a native clz instruction nor a native
+ * ctz instruction, gcc resolves __builtin_clz to __clzdi2 rather than
+ * __clzsi2, leading to infinite recursion. */
#define __builtin_clz(a) __clzsi2(a)
extern si_int __clzsi2(si_int);
#endif
diff --git a/lib/builtins/ctzdi2.c b/lib/builtins/ctzdi2.c
index eecde29..ef6d7fe 100644
--- a/lib/builtins/ctzdi2.c
+++ b/lib/builtins/ctzdi2.c
@@ -16,8 +16,13 @@
/* Returns: the number of trailing 0-bits */
-#if !defined(__clang__) && (defined(__sparc64__) || defined(__mips64) || defined(__riscv__))
-/* gcc resolves __builtin_ctz -> __ctzdi2 leading to infinite recursion */
+#if !defined(__clang__) && \
+ ((defined(__sparc__) && defined(__arch64__)) || \
+ defined(__mips64) || \
+ (defined(__riscv) && __SIZEOF_POINTER__ >= 8))
+/* On 64-bit architectures with neither a native clz instruction nor a native
+ * ctz instruction, gcc resolves __builtin_ctz to __ctzdi2 rather than
+ * __ctzsi2, leading to infinite recursion. */
#define __builtin_ctz(a) __ctzsi2(a)
extern si_int __ctzsi2(si_int);
#endif
