[llvm] [LLVM][Instrumentation] Add numerical sanitizer (PR #85916)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,20 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -passes=nsan -nsan-shadow-type-mapping=dqq -nsan-propagate-non-ft-const-stores-as-ft -S %s | FileCheck %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+
+define void @store_non_float(ptr %dst) sanitize_numericalstability {
+; CHECK-LABEL: @store_non_float(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    store i32 42, ptr [[DST:%.*]], align 1
+; CHECK-NEXT:    [[TMP0:%.*]] = call ptr @__nsan_get_shadow_ptr_for_float_store(ptr [[DST]], i64 1)
+; CHECK-NEXT:    store double 0x36F5000000000000, ptr [[TMP0]], align 1
+; CHECK-NEXT:    ret void
+;
+entry:
+  store i32 42, ptr %dst, align 1
+  ret void
+}
+
+attributes #0 = { nounwind readonly uwtable sanitize_numericalstability "correctly-rounded-divide-sqrt-fp-math"="false" "denormal-fp-math"="preserve-sign,preserve-sign" "denormal-fp-math-f32"="ieee,ieee" "disable-tail-calls"="false" "frame-pointer"="none" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="true" "no-jump-tables"="false" "no-nans-fp-math"="true" "no-signed-zeros-fp-math"="true" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="true" "use-soft-float"="false" }
+
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MaskRay wrote:

delete unneeded trailing blank lines

ditto elsewhere

https://github.com/llvm/llvm-project/pull/85916