ARM: Move remaining half convert libcall config into tablegen #153408
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This was referenced Aug 13, 2025
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@llvm/pr-subscribers-backend-arm @llvm/pr-subscribers-llvm-ir Author: Matt Arsenault (arsenm) ChangesThe __truncdfhf2 handling is kind of convoluted, but reproduces Full diff: https://github.com/llvm/llvm-project/pull/153408.diff 2 Files Affected:
diff --git a/llvm/include/llvm/IR/RuntimeLibcalls.td b/llvm/include/llvm/IR/RuntimeLibcalls.td
index 89bb0be4d26e9..a98e94455dd21 100644
--- a/llvm/include/llvm/IR/RuntimeLibcalls.td
+++ b/llvm/include/llvm/IR/RuntimeLibcalls.td
@@ -1532,10 +1532,17 @@ def ARMHalfConvertLibcallCallingConv : LibcallCallingConv<
(isAAPCS_ABI(TT, ABIName) ? CallingConv::ARM_AAPCS : CallingConv::ARM_APCS)}]
>;
-def GNUEABIHalfConvertCalls :
- LibcallImpls<(add __gnu_f2h_ieee, __gnu_h2f_ieee),
- RuntimeLibcallPredicate<[{!TT.isOSBinFormatMachO() &&
- !TT.isTargetAEABI()}]>> {
+def ARMLibgccHalfConvertCalls :
+ LibcallImpls<(add __truncsfhf2, __extendhfsf2),
+ RuntimeLibcallPredicate<[{!TT.isTargetAEABI() && TT.isOSBinFormatMachO()}]>> {
+ let CallingConv = ARMHalfConvertLibcallCallingConv;
+}
+
+// FIXME: These conditions are probably bugged. We're using the
+// default libgcc call when the other cases are replaced.
+def ARMDoubleToHalfCalls :
+ LibcallImpls<(add __truncdfhf2),
+ RuntimeLibcallPredicate<[{!TT.isTargetAEABI()}]>> {
let CallingConv = ARMHalfConvertLibcallCallingConv;
}
@@ -1546,6 +1553,13 @@ def EABIHalfConvertCalls : LibcallImpls<(add __aeabi_f2h, __aeabi_h2f),
let CallingConv = ARM_AAPCS;
}
+def GNUEABIHalfConvertCalls :
+ LibcallImpls<(add __gnu_f2h_ieee, __gnu_h2f_ieee),
+ RuntimeLibcallPredicate<[{!TT.isOSBinFormatMachO() &&
+ !TT.isTargetAEABI()}]>> {
+ let CallingConv = ARMHalfConvertLibcallCallingConv;
+}
+
def WindowARMDivRemCalls : LibcallImpls<
(add __rt_sdiv, __rt_sdiv64, __rt_udiv, __rt_udiv64),
isOSWindows> {
@@ -1665,7 +1679,9 @@ def isARMOrThumb : RuntimeLibcallPredicate<"TT.isARM() || TT.isThumb()">;
def ARMSystemLibrary
: SystemRuntimeLibrary<isARMOrThumb,
- (add WinDefaultLibcallImpls,
+ (add (sub WinDefaultLibcallImpls, ARMLibgccHalfConvertCalls,
+ GNUEABIHalfConvertCalls,
+ ARMDoubleToHalfCalls),
LibcallImpls<(add __powisf2, __powidf2), isNotOSMSVCRT>,
LibmHasFrexpF32, LibmHasLdexpF32,
LibmHasFrexpF128, LibmHasLdexpF128,
@@ -1679,8 +1695,10 @@ def ARMSystemLibrary
AEABICalls,
AEABI45MemCalls,
+ ARMLibgccHalfConvertCalls,
EABIHalfConvertCalls,
GNUEABIHalfConvertCalls,
+ ARMDoubleToHalfCalls,
// Use divmod compiler-rt calls for iOS 5.0 and later.
LibcallImpls<(add __divmodsi4, __udivmodsi4),
diff --git a/llvm/lib/IR/RuntimeLibcalls.cpp b/llvm/lib/IR/RuntimeLibcalls.cpp
index ac845c4998783..83f7df5e9f587 100644
--- a/llvm/lib/IR/RuntimeLibcalls.cpp
+++ b/llvm/lib/IR/RuntimeLibcalls.cpp
@@ -33,25 +33,6 @@ void RuntimeLibcallsInfo::initLibcalls(const Triple &TT,
if (ExceptionModel == ExceptionHandling::SjLj)
setLibcallImpl(RTLIB::UNWIND_RESUME, RTLIB::_Unwind_SjLj_Resume);
- if (TT.isARM() || TT.isThumb()) {
- // The half <-> float conversion functions are always soft-float on
- // non-watchos platforms, but are needed for some targets which use a
- // hard-float calling convention by default.
- if (!TT.isWatchABI()) {
- if (isAAPCS_ABI(TT, ABIName)) {
- setLibcallImplCallingConv(RTLIB::__truncsfhf2, CallingConv::ARM_AAPCS);
- setLibcallImplCallingConv(RTLIB::__truncdfhf2, CallingConv::ARM_AAPCS);
- setLibcallImplCallingConv(RTLIB::__extendhfsf2, CallingConv::ARM_AAPCS);
- } else {
- setLibcallImplCallingConv(RTLIB::__truncsfhf2, CallingConv::ARM_APCS);
- setLibcallImplCallingConv(RTLIB::__truncdfhf2, CallingConv::ARM_APCS);
- setLibcallImplCallingConv(RTLIB::__extendhfsf2, CallingConv::ARM_APCS);
- }
- }
-
- return;
- }
-
if (TT.getArch() == Triple::ArchType::msp430) {
setLibcallImplCallingConv(RTLIB::__mspabi_mpyll,
CallingConv::MSP430_BUILTIN);
|
|
@llvm/pr-subscribers-tablegen Author: Matt Arsenault (arsenm) ChangesThe __truncdfhf2 handling is kind of convoluted, but reproduces Full diff: https://github.com/llvm/llvm-project/pull/153408.diff 2 Files Affected:
diff --git a/llvm/include/llvm/IR/RuntimeLibcalls.td b/llvm/include/llvm/IR/RuntimeLibcalls.td
index 89bb0be4d26e9..a98e94455dd21 100644
--- a/llvm/include/llvm/IR/RuntimeLibcalls.td
+++ b/llvm/include/llvm/IR/RuntimeLibcalls.td
@@ -1532,10 +1532,17 @@ def ARMHalfConvertLibcallCallingConv : LibcallCallingConv<
(isAAPCS_ABI(TT, ABIName) ? CallingConv::ARM_AAPCS : CallingConv::ARM_APCS)}]
>;
-def GNUEABIHalfConvertCalls :
- LibcallImpls<(add __gnu_f2h_ieee, __gnu_h2f_ieee),
- RuntimeLibcallPredicate<[{!TT.isOSBinFormatMachO() &&
- !TT.isTargetAEABI()}]>> {
+def ARMLibgccHalfConvertCalls :
+ LibcallImpls<(add __truncsfhf2, __extendhfsf2),
+ RuntimeLibcallPredicate<[{!TT.isTargetAEABI() && TT.isOSBinFormatMachO()}]>> {
+ let CallingConv = ARMHalfConvertLibcallCallingConv;
+}
+
+// FIXME: These conditions are probably bugged. We're using the
+// default libgcc call when the other cases are replaced.
+def ARMDoubleToHalfCalls :
+ LibcallImpls<(add __truncdfhf2),
+ RuntimeLibcallPredicate<[{!TT.isTargetAEABI()}]>> {
let CallingConv = ARMHalfConvertLibcallCallingConv;
}
@@ -1546,6 +1553,13 @@ def EABIHalfConvertCalls : LibcallImpls<(add __aeabi_f2h, __aeabi_h2f),
let CallingConv = ARM_AAPCS;
}
+def GNUEABIHalfConvertCalls :
+ LibcallImpls<(add __gnu_f2h_ieee, __gnu_h2f_ieee),
+ RuntimeLibcallPredicate<[{!TT.isOSBinFormatMachO() &&
+ !TT.isTargetAEABI()}]>> {
+ let CallingConv = ARMHalfConvertLibcallCallingConv;
+}
+
def WindowARMDivRemCalls : LibcallImpls<
(add __rt_sdiv, __rt_sdiv64, __rt_udiv, __rt_udiv64),
isOSWindows> {
@@ -1665,7 +1679,9 @@ def isARMOrThumb : RuntimeLibcallPredicate<"TT.isARM() || TT.isThumb()">;
def ARMSystemLibrary
: SystemRuntimeLibrary<isARMOrThumb,
- (add WinDefaultLibcallImpls,
+ (add (sub WinDefaultLibcallImpls, ARMLibgccHalfConvertCalls,
+ GNUEABIHalfConvertCalls,
+ ARMDoubleToHalfCalls),
LibcallImpls<(add __powisf2, __powidf2), isNotOSMSVCRT>,
LibmHasFrexpF32, LibmHasLdexpF32,
LibmHasFrexpF128, LibmHasLdexpF128,
@@ -1679,8 +1695,10 @@ def ARMSystemLibrary
AEABICalls,
AEABI45MemCalls,
+ ARMLibgccHalfConvertCalls,
EABIHalfConvertCalls,
GNUEABIHalfConvertCalls,
+ ARMDoubleToHalfCalls,
// Use divmod compiler-rt calls for iOS 5.0 and later.
LibcallImpls<(add __divmodsi4, __udivmodsi4),
diff --git a/llvm/lib/IR/RuntimeLibcalls.cpp b/llvm/lib/IR/RuntimeLibcalls.cpp
index ac845c4998783..83f7df5e9f587 100644
--- a/llvm/lib/IR/RuntimeLibcalls.cpp
+++ b/llvm/lib/IR/RuntimeLibcalls.cpp
@@ -33,25 +33,6 @@ void RuntimeLibcallsInfo::initLibcalls(const Triple &TT,
if (ExceptionModel == ExceptionHandling::SjLj)
setLibcallImpl(RTLIB::UNWIND_RESUME, RTLIB::_Unwind_SjLj_Resume);
- if (TT.isARM() || TT.isThumb()) {
- // The half <-> float conversion functions are always soft-float on
- // non-watchos platforms, but are needed for some targets which use a
- // hard-float calling convention by default.
- if (!TT.isWatchABI()) {
- if (isAAPCS_ABI(TT, ABIName)) {
- setLibcallImplCallingConv(RTLIB::__truncsfhf2, CallingConv::ARM_AAPCS);
- setLibcallImplCallingConv(RTLIB::__truncdfhf2, CallingConv::ARM_AAPCS);
- setLibcallImplCallingConv(RTLIB::__extendhfsf2, CallingConv::ARM_AAPCS);
- } else {
- setLibcallImplCallingConv(RTLIB::__truncsfhf2, CallingConv::ARM_APCS);
- setLibcallImplCallingConv(RTLIB::__truncdfhf2, CallingConv::ARM_APCS);
- setLibcallImplCallingConv(RTLIB::__extendhfsf2, CallingConv::ARM_APCS);
- }
- }
-
- return;
- }
-
if (TT.getArch() == Triple::ArchType::msp430) {
setLibcallImplCallingConv(RTLIB::__mspabi_mpyll,
CallingConv::MSP430_BUILTIN);
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Base automatically changed from
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Aug 15, 2025
| @@ -1497,6 +1490,27 @@ def ARMHalfConvertLibcallCallingConv : LibcallCallingConv< | |||
| (isAAPCS_ABI(TT, ABIName) ? CallingConv::ARM_AAPCS : CallingConv::ARM_APCS)}] | |||
| >; | |||
|
|
|||
| def ARMLibgccHalfConvertCalls : | |||
| LibcallImpls<(add __truncsfhf2, __extendhfsf2), | |||
| RuntimeLibcallPredicate<[{!TT.isTargetAEABI() && TT.isOSBinFormatMachO()}]>> { | |||
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I'm not sure I follow this - the old code would add these on !Watch ABI as either AAPCS or APCS.
There was a problem hiding this comment.
These are the default values, and !WatchABI is not mutually exclusive. This needs to be expressed as the positive set of cases where it is used
There was a problem hiding this comment.
Sure, but what I mean to say is that this feels like it applies to far more cases than previously.
| // default libgcc call when the other cases are replaced. | ||
| def ARMDoubleToHalfCalls : | ||
| LibcallImpls<(add __truncdfhf2), | ||
| RuntimeLibcallPredicate<[{!TT.isTargetAEABI()}]>> { |
The __truncdfhf2 handling is kind of convoluted, but reproduces the existing, likely wrong, handling.
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The __truncdfhf2 handling is kind of convoluted, but reproduces
the existing, likely wrong, handling.