From c87ec61a42345b2260ac52902b4544fbb57f99e3 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Sat, 23 Mar 2024 11:32:36 +0100
Subject: [PATCH] add support for missing SIMD float intrinsics

---
 src/tools/miri/src/shims/intrinsics/simd.rs | 44 +++++++++++++++++----
 src/tools/miri/tests/pass/portable-simd.rs  | 18 +++++++++
 2 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/src/tools/miri/src/shims/intrinsics/simd.rs b/src/tools/miri/src/shims/intrinsics/simd.rs
index c97a052f517..af98b38af8c 100644
--- a/src/tools/miri/src/shims/intrinsics/simd.rs
+++ b/src/tools/miri/src/shims/intrinsics/simd.rs
@@ -33,6 +33,13 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             | "round"
             | "trunc"
             | "fsqrt"
+            | "fsin"
+            | "fcos"
+            | "fexp"
+            | "fexp2"
+            | "flog"
+            | "flog2"
+            | "flog10"
             | "ctlz"
             | "cttz"
             | "bswap"
@@ -45,17 +52,16 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                 assert_eq!(dest_len, op_len);
 
                 #[derive(Copy, Clone)]
-                enum Op {
+                enum Op<'a> {
                     MirOp(mir::UnOp),
                     Abs,
-                    Sqrt,
                     Round(rustc_apfloat::Round),
                     Numeric(Symbol),
+                    HostOp(&'a str),
                 }
                 let which = match intrinsic_name {
                     "neg" => Op::MirOp(mir::UnOp::Neg),
                     "fabs" => Op::Abs,
-                    "fsqrt" => Op::Sqrt,
                     "ceil" => Op::Round(rustc_apfloat::Round::TowardPositive),
                     "floor" => Op::Round(rustc_apfloat::Round::TowardNegative),
                     "round" => Op::Round(rustc_apfloat::Round::NearestTiesToAway),
@@ -64,7 +70,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     "cttz" => Op::Numeric(sym::cttz),
                     "bswap" => Op::Numeric(sym::bswap),
                     "bitreverse" => Op::Numeric(sym::bitreverse),
-                    _ => unreachable!(),
+                    _ => Op::HostOp(intrinsic_name),
                 };
 
                 for i in 0..dest_len {
@@ -89,7 +95,7 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                                 FloatTy::F128 => unimplemented!("f16_f128"),
                             }
                         }
-                        Op::Sqrt => {
+                        Op::HostOp(host_op) => {
                             let ty::Float(float_ty) = op.layout.ty.kind() else {
                                 span_bug!(this.cur_span(), "{} operand is not a float", intrinsic_name)
                             };
@@ -98,13 +104,37 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                                 FloatTy::F16 => unimplemented!("f16_f128"),
                                 FloatTy::F32 => {
                                     let f = op.to_scalar().to_f32()?;
-                                    let res = f.to_host().sqrt().to_soft();
+                                    let f_host = f.to_host();
+                                    let res = match host_op {
+                                        "fsqrt" => f_host.sqrt(),
+                                        "fsin" => f_host.sin(),
+                                        "fcos" => f_host.cos(),
+                                        "fexp" => f_host.exp(),
+                                        "fexp2" => f_host.exp2(),
+                                        "flog" => f_host.ln(),
+                                        "flog2" => f_host.log2(),
+                                        "flog10" => f_host.log10(),
+                                        _ => bug!(),
+                                    };
+                                    let res = res.to_soft();
                                     let res = this.adjust_nan(res, &[f]);
                                     Scalar::from(res)
                                 }
                                 FloatTy::F64 => {
                                     let f = op.to_scalar().to_f64()?;
-                                    let res = f.to_host().sqrt().to_soft();
+                                    let f_host = f.to_host();
+                                    let res = match host_op {
+                                        "fsqrt" => f_host.sqrt(),
+                                        "fsin" => f_host.sin(),
+                                        "fcos" => f_host.cos(),
+                                        "fexp" => f_host.exp(),
+                                        "fexp2" => f_host.exp2(),
+                                        "flog" => f_host.ln(),
+                                        "flog2" => f_host.log2(),
+                                        "flog10" => f_host.log10(),
+                                        _ => bug!(),
+                                    };
+                                    let res = res.to_soft();
                                     let res = this.adjust_nan(res, &[f]);
                                     Scalar::from(res)
                                 }
diff --git a/src/tools/miri/tests/pass/portable-simd.rs b/src/tools/miri/tests/pass/portable-simd.rs
index 399913a757b..cdb441b450b 100644
--- a/src/tools/miri/tests/pass/portable-simd.rs
+++ b/src/tools/miri/tests/pass/portable-simd.rs
@@ -526,6 +526,23 @@ fn simd_intrinsics() {
     }
 }
 
+fn simd_float_intrinsics() {
+    use intrinsics::*;
+
+    // These are just smoke tests to ensure the intrinsics can be called.
+    unsafe {
+        let a = f32x4::splat(10.0);
+        simd_fsqrt(a);
+        simd_fsin(a);
+        simd_fcos(a);
+        simd_fexp(a);
+        simd_fexp2(a);
+        simd_flog(a);
+        simd_flog2(a);
+        simd_flog10(a);
+    }
+}
+
 fn simd_masked_loadstore() {
     // The buffer is deliberarely too short, so reading the last element would be UB.
     let buf = [3i32; 3];
@@ -559,5 +576,6 @@ fn main() {
     simd_gather_scatter();
     simd_round();
     simd_intrinsics();
+    simd_float_intrinsics();
     simd_masked_loadstore();
 }