[llvm] 39e5dd1 - [SparcISelLowering] avoid emitting libcalls to __muloti4 and __mulodi4

[Nick Desaulniers via llvm-commits]

Author: Nick Desaulniers
Date: 2021-10-29T13:14:09-07:00
New Revision: 39e5dd113f5c00de21f8071142fccbb5e08025e7

URL: https://github.com/llvm/llvm-project/commit/39e5dd113f5c00de21f8071142fccbb5e08025e7
DIFF: https://github.com/llvm/llvm-project/commit/39e5dd113f5c00de21f8071142fccbb5e08025e7.diff

LOG: [SparcISelLowering] avoid emitting libcalls to __muloti4 and __mulodi4

These compiler-rt-only symbols aren't available in libgcc.  Similar to
D108842, D108844, and D108926.

Fixes: pr/52043

Reviewed By: craig.topper, rengolin

Differential Revision: https://reviews.llvm.org/D112750

Added: 
    llvm/test/CodeGen/SPARC/overflow-intrinsic-optimizations.ll

Modified: 
    llvm/lib/Target/Sparc/SparcISelLowering.cpp

Removed: 
    


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diff  --git a/llvm/lib/Target/Sparc/SparcISelLowering.cpp b/llvm/lib/Target/Sparc/SparcISelLowering.cpp
index 2007303d99035..70c2c7bbde870 100644
--- a/llvm/lib/Target/Sparc/SparcISelLowering.cpp
+++ b/llvm/lib/Target/Sparc/SparcISelLowering.cpp
@@ -1614,11 +1614,14 @@ SparcTargetLowering::SparcTargetLowering(const TargetMachine &TM,
 
   if (!Subtarget->is64Bit()) {
     // These libcalls are not available in 32-bit.
+    setLibcallName(RTLIB::MULO_I64, nullptr);
     setLibcallName(RTLIB::SHL_I128, nullptr);
     setLibcallName(RTLIB::SRL_I128, nullptr);
     setLibcallName(RTLIB::SRA_I128, nullptr);
   }
 
+  setLibcallName(RTLIB::MULO_I128, nullptr);
+
   if (!Subtarget->isV9()) {
     // SparcV8 does not have FNEGD and FABSD.
     setOperationAction(ISD::FNEG, MVT::f64, Custom);

diff  --git a/llvm/test/CodeGen/SPARC/overflow-intrinsic-optimizations.ll b/llvm/test/CodeGen/SPARC/overflow-intrinsic-optimizations.ll
new file mode 100644
index 0000000000000..a782aa12bd322
--- /dev/null
+++ b/llvm/test/CodeGen/SPARC/overflow-intrinsic-optimizations.ll
@@ -0,0 +1,28 @@
+; RUN: llc %s -mtriple=sparc -o - | FileCheck %s
+; RUN: llc %s -mtriple=sparc64 -o - | FileCheck %s
+declare { i128, i1 } @llvm.smul.with.overflow.i128(i128, i128)
+declare { i64, i1 } @llvm.smul.with.overflow.i64(i64, i64)
+
+define i32 @mul(i128 %a, i128 %b, i128* %r) {
+; CHECK-LABEL: mul
+; CHECK-NOT: call __muloti4
+  %mul4 = tail call { i128, i1 } @llvm.smul.with.overflow.i128(i128 %a, i128 %b)
+  %mul.val = extractvalue { i128, i1 } %mul4, 0
+  %mul.ov = extractvalue { i128, i1 } %mul4, 1
+  %mul.not.ov = xor i1 %mul.ov, true
+  store i128 %mul.val, i128* %r, align 16
+  %conv = zext i1 %mul.not.ov to i32
+  ret i32 %conv
+}
+
+define i32 @mul2(i64 %a, i64 %b, i64* %r) {
+; CHECK-LABEL: mul2
+; CHECK-NOT: call __mulodi4
+  %mul4 = tail call { i64, i1 } @llvm.smul.with.overflow.i64(i64 %a, i64 %b)
+  %mul.val = extractvalue { i64, i1 } %mul4, 0
+  %mul.ov = extractvalue { i64, i1 } %mul4, 1
+  %mul.not.ov = xor i1 %mul.ov, true
+  store i64 %mul.val, i64* %r, align 16
+  %conv = zext i1 %mul.not.ov to i32
+  ret i32 %conv
+}