[CodeGen] convert math libcalls/builtins to equivalent LLVM intrinsics
There are 20 LLVM math intrinsics that correspond to mathlib calls according to the LangRef:
http://llvm.org/docs/LangRef.html#standard-c-library-intrinsics
We were only converting 3 mathlib calls (sqrt, fma, pow) and 12 builtin calls (ceil, copysign,
fabs, floor, fma, fmax, fmin, nearbyint, pow, rint, round, trunc) to their intrinsic-equivalents.
This patch pulls the transforms together and handles all 20 cases. The switch is guarded by a
check for const-ness to make sure we're not doing the transform if errno could possibly be set by
the libcall or builtin.
Differential Revision: https://reviews.llvm.org/D40044
llvm-svn: 319593
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 34adc64..76b6db1 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -854,6 +854,179 @@
Result.Val.getFloat()));
}
+ // Math builtins have the same semantics as their math library twins.
+ // There are LLVM math intrinsics corresponding to math library functions
+ // except the intrinsic will never set errno while the math library might.
+ // Thus, we can transform math library and builtin calls to their
+ // semantically-equivalent LLVM intrinsic counterparts if the call is marked
+ // 'const' (it is known to never set errno).
+ if (FD->hasAttr<ConstAttr>()) {
+ switch (BuiltinID) {
+ case Builtin::BIceil:
+ case Builtin::BIceilf:
+ case Builtin::BIceill:
+ case Builtin::BI__builtin_ceil:
+ case Builtin::BI__builtin_ceilf:
+ case Builtin::BI__builtin_ceill:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::ceil));
+
+ case Builtin::BIcopysign:
+ case Builtin::BIcopysignf:
+ case Builtin::BIcopysignl:
+ case Builtin::BI__builtin_copysign:
+ case Builtin::BI__builtin_copysignf:
+ case Builtin::BI__builtin_copysignl:
+ return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::copysign));
+
+ case Builtin::BIcos:
+ case Builtin::BIcosf:
+ case Builtin::BIcosl:
+ case Builtin::BI__builtin_cos:
+ case Builtin::BI__builtin_cosf:
+ case Builtin::BI__builtin_cosl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::cos));
+
+ case Builtin::BIexp:
+ case Builtin::BIexpf:
+ case Builtin::BIexpl:
+ case Builtin::BI__builtin_exp:
+ case Builtin::BI__builtin_expf:
+ case Builtin::BI__builtin_expl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::exp));
+
+ case Builtin::BIexp2:
+ case Builtin::BIexp2f:
+ case Builtin::BIexp2l:
+ case Builtin::BI__builtin_exp2:
+ case Builtin::BI__builtin_exp2f:
+ case Builtin::BI__builtin_exp2l:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::exp2));
+
+ case Builtin::BIfabs:
+ case Builtin::BIfabsf:
+ case Builtin::BIfabsl:
+ case Builtin::BI__builtin_fabs:
+ case Builtin::BI__builtin_fabsf:
+ case Builtin::BI__builtin_fabsl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::fabs));
+
+ case Builtin::BIfloor:
+ case Builtin::BIfloorf:
+ case Builtin::BIfloorl:
+ case Builtin::BI__builtin_floor:
+ case Builtin::BI__builtin_floorf:
+ case Builtin::BI__builtin_floorl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::floor));
+
+ case Builtin::BIfma:
+ case Builtin::BIfmaf:
+ case Builtin::BIfmal:
+ case Builtin::BI__builtin_fma:
+ case Builtin::BI__builtin_fmaf:
+ case Builtin::BI__builtin_fmal:
+ return RValue::get(emitTernaryBuiltin(*this, E, Intrinsic::fma));
+
+ case Builtin::BIfmax:
+ case Builtin::BIfmaxf:
+ case Builtin::BIfmaxl:
+ case Builtin::BI__builtin_fmax:
+ case Builtin::BI__builtin_fmaxf:
+ case Builtin::BI__builtin_fmaxl:
+ return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::maxnum));
+
+ case Builtin::BIfmin:
+ case Builtin::BIfminf:
+ case Builtin::BIfminl:
+ case Builtin::BI__builtin_fmin:
+ case Builtin::BI__builtin_fminf:
+ case Builtin::BI__builtin_fminl:
+ return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::minnum));
+
+ case Builtin::BIlog:
+ case Builtin::BIlogf:
+ case Builtin::BIlogl:
+ case Builtin::BI__builtin_log:
+ case Builtin::BI__builtin_logf:
+ case Builtin::BI__builtin_logl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::log));
+
+ case Builtin::BIlog10:
+ case Builtin::BIlog10f:
+ case Builtin::BIlog10l:
+ case Builtin::BI__builtin_log10:
+ case Builtin::BI__builtin_log10f:
+ case Builtin::BI__builtin_log10l:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::log10));
+
+ case Builtin::BIlog2:
+ case Builtin::BIlog2f:
+ case Builtin::BIlog2l:
+ case Builtin::BI__builtin_log2:
+ case Builtin::BI__builtin_log2f:
+ case Builtin::BI__builtin_log2l:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::log2));
+
+ case Builtin::BInearbyint:
+ case Builtin::BInearbyintf:
+ case Builtin::BInearbyintl:
+ case Builtin::BI__builtin_nearbyint:
+ case Builtin::BI__builtin_nearbyintf:
+ case Builtin::BI__builtin_nearbyintl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::nearbyint));
+
+ case Builtin::BIpow:
+ case Builtin::BIpowf:
+ case Builtin::BIpowl:
+ case Builtin::BI__builtin_pow:
+ case Builtin::BI__builtin_powf:
+ case Builtin::BI__builtin_powl:
+ return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::pow));
+
+ case Builtin::BIrint:
+ case Builtin::BIrintf:
+ case Builtin::BIrintl:
+ case Builtin::BI__builtin_rint:
+ case Builtin::BI__builtin_rintf:
+ case Builtin::BI__builtin_rintl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::rint));
+
+ case Builtin::BIround:
+ case Builtin::BIroundf:
+ case Builtin::BIroundl:
+ case Builtin::BI__builtin_round:
+ case Builtin::BI__builtin_roundf:
+ case Builtin::BI__builtin_roundl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::round));
+
+ case Builtin::BIsin:
+ case Builtin::BIsinf:
+ case Builtin::BIsinl:
+ case Builtin::BI__builtin_sin:
+ case Builtin::BI__builtin_sinf:
+ case Builtin::BI__builtin_sinl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::sin));
+
+ case Builtin::BIsqrt:
+ case Builtin::BIsqrtf:
+ case Builtin::BIsqrtl:
+ case Builtin::BI__builtin_sqrt:
+ case Builtin::BI__builtin_sqrtf:
+ case Builtin::BI__builtin_sqrtl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::sqrt));
+
+ case Builtin::BItrunc:
+ case Builtin::BItruncf:
+ case Builtin::BItruncl:
+ case Builtin::BI__builtin_trunc:
+ case Builtin::BI__builtin_truncf:
+ case Builtin::BI__builtin_truncl:
+ return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::trunc));
+
+ default:
+ break;
+ }
+ }
+
switch (BuiltinID) {
default: break; // Handle intrinsics and libm functions below.
case Builtin::BI__builtin___CFStringMakeConstantString:
@@ -894,11 +1067,6 @@
return RValue::get(Result);
}
- case Builtin::BI__builtin_fabs:
- case Builtin::BI__builtin_fabsf:
- case Builtin::BI__builtin_fabsl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::fabs));
- }
case Builtin::BI__builtin_fmod:
case Builtin::BI__builtin_fmodf:
case Builtin::BI__builtin_fmodl: {
@@ -907,51 +1075,6 @@
Value *Result = Builder.CreateFRem(Arg1, Arg2, "fmod");
return RValue::get(Result);
}
- case Builtin::BI__builtin_copysign:
- case Builtin::BI__builtin_copysignf:
- case Builtin::BI__builtin_copysignl: {
- return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::copysign));
- }
- case Builtin::BI__builtin_ceil:
- case Builtin::BI__builtin_ceilf:
- case Builtin::BI__builtin_ceill: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::ceil));
- }
- case Builtin::BI__builtin_floor:
- case Builtin::BI__builtin_floorf:
- case Builtin::BI__builtin_floorl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::floor));
- }
- case Builtin::BI__builtin_trunc:
- case Builtin::BI__builtin_truncf:
- case Builtin::BI__builtin_truncl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::trunc));
- }
- case Builtin::BI__builtin_rint:
- case Builtin::BI__builtin_rintf:
- case Builtin::BI__builtin_rintl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::rint));
- }
- case Builtin::BI__builtin_nearbyint:
- case Builtin::BI__builtin_nearbyintf:
- case Builtin::BI__builtin_nearbyintl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::nearbyint));
- }
- case Builtin::BI__builtin_round:
- case Builtin::BI__builtin_roundf:
- case Builtin::BI__builtin_roundl: {
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::round));
- }
- case Builtin::BI__builtin_fmin:
- case Builtin::BI__builtin_fminf:
- case Builtin::BI__builtin_fminl: {
- return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::minnum));
- }
- case Builtin::BI__builtin_fmax:
- case Builtin::BI__builtin_fmaxf:
- case Builtin::BI__builtin_fmaxl: {
- return RValue::get(emitBinaryBuiltin(*this, E, Intrinsic::maxnum));
- }
case Builtin::BI__builtin_conj:
case Builtin::BI__builtin_conjf:
case Builtin::BI__builtin_conjl: {
@@ -2073,49 +2196,6 @@
return RValue::get(nullptr);
}
- case Builtin::BIsqrt:
- case Builtin::BIsqrtf:
- case Builtin::BIsqrtl:
- // Builtins have the same semantics as library functions. The LLVM intrinsic
- // has the same semantics as the library function except it does not set
- // errno. Thus, we can transform either sqrt or __builtin_sqrt to @llvm.sqrt
- // if the call is 'const' (the call must not set errno).
- //
- // FIXME: The builtin cases are not here because they are marked 'const' in
- // Builtins.def. So that means they are wrongly defined to have different
- // semantics than the library functions. If we included them here, we would
- // turn them into LLVM intrinsics regardless of whether -fmath-errno was on.
- if (FD->hasAttr<ConstAttr>())
- return RValue::get(emitUnaryBuiltin(*this, E, Intrinsic::sqrt));
- break;
-
- case Builtin::BI__builtin_pow:
- case Builtin::BI__builtin_powf:
- case Builtin::BI__builtin_powl:
- case Builtin::BIpow:
- case Builtin::BIpowf:
- case Builtin::BIpowl: {
- // Transform a call to pow* into a @llvm.pow.* intrinsic call.
- if (!FD->hasAttr<ConstAttr>())
- break;
- Value *Base = EmitScalarExpr(E->getArg(0));
- Value *Exponent = EmitScalarExpr(E->getArg(1));
- llvm::Type *ArgType = Base->getType();
- Value *F = CGM.getIntrinsic(Intrinsic::pow, ArgType);
- return RValue::get(Builder.CreateCall(F, {Base, Exponent}));
- }
-
- case Builtin::BIfma:
- case Builtin::BIfmaf:
- case Builtin::BIfmal:
- case Builtin::BI__builtin_fma:
- case Builtin::BI__builtin_fmaf:
- case Builtin::BI__builtin_fmal:
- // A constant libcall or builtin is equivalent to the LLVM intrinsic.
- if (FD->hasAttr<ConstAttr>())
- return RValue::get(emitTernaryBuiltin(*this, E, Intrinsic::fma));
- break;
-
case Builtin::BI__builtin_signbit:
case Builtin::BI__builtin_signbitf:
case Builtin::BI__builtin_signbitl: {