[llvm] [X86] Combine FRINT + FP_TO_SINT to LRINT (PR #126477)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,51 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc < %s -mtriple=i686-unknown -mattr=+sse2 | FileCheck %s --check-prefixes=X86
+; RUN: llc < %s -mtriple=x86_64-unknown | FileCheck %s --check-prefixes=X64
+
+define i32 @combine_f32(float %x) nounwind {
+; X86-LABEL: combine_f32:
+; X86:       # %bb.0: # %entry
+; X86-NEXT:    cvtss2si {{[0-9]+}}(%esp), %eax
+; X86-NEXT:    retl
+;
+; X64-LABEL: combine_f32:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    cvtss2si %xmm0, %eax
+; X64-NEXT:    retq
+entry:
+  %0 = tail call float @llvm.rint.f32(float %x)
+  %1 = fptosi float %0 to i32
+  ret i32 %1
+}
+
+define i32 @combine_f64(double %x) nounwind {
+; X86-LABEL: combine_f64:
+; X86:       # %bb.0: # %entry
+; X86-NEXT:    cvtsd2si {{[0-9]+}}(%esp), %eax
+; X86-NEXT:    retl
+;
+; X64-LABEL: combine_f64:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    cvtsd2si %xmm0, %eax
+; X64-NEXT:    retq
+entry:
+  %0 = tail call double @llvm.rint.f32(double %x)
+  %1 = fptosi double %0 to i32
+  ret i32 %1
+}
+
+define <4 x i32> @combine_v4f32(<4 x float> %x) nounwind {
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RKSimon wrote:

Add v2f64 / v4f64 cases and AVX test coverage?

https://github.com/llvm/llvm-project/pull/126477