Add scalar lowering for sqrt intrinsic.

tests_lit/llvm2ice_tests/nacl-other-intrinsics.ll

 ; This tests the NaCl intrinsics not related to atomic operations.
 
 ; RUN: %llvm2ice -O2 --verbose none %s | FileCheck %s
 ; RUN: %llvm2ice -O2 --verbose none %s | FileCheck %s --check-prefix=CHECKO2REM
 ; RUN: %llvm2ice -Om1 --verbose none %s | FileCheck %s
 ; RUN: %llvm2ice --verbose none %s | FileCheck --check-prefix=ERRORS %s
 
 ; RUN: %llvm2iceinsts %s | %szdiff %s | FileCheck --check-prefix=DUMP %s
 ; RUN: %llvm2iceinsts --pnacl %s | %szdiff %s \
 ; RUN:                           | FileCheck --check-prefix=DUMP %s
 
 declare i8* @llvm.nacl.read.tp()
 declare void @llvm.memcpy.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
 declare void @llvm.memmove.p0i8.p0i8.i32(i8*, i8*, i32, i32, i1)
 declare void @llvm.memset.p0i8.i32(i8*, i8, i32, i32, i1)
 declare void @llvm.nacl.longjmp(i8*, i32)
 declare i32 @llvm.nacl.setjmp(i8*)
+declare float @llvm.sqrt.f32(float)
+declare double @llvm.sqrt.f64(double)
 declare void @llvm.trap()
 
 define i32 @test_nacl_read_tp() {
 entry:
   %ptr = call i8* @llvm.nacl.read.tp()
   %__1 = ptrtoint i8* %ptr to i32
   ret i32 %__1
 }
 ; CHECK-LABEL: test_nacl_read_tp
 ; CHECK: mov e{{.*}}, dword ptr gs:[0]
@@ skipping 125 matching lines @@
 entry:
   %env = inttoptr i32 %iptr_env to i8*
   %i = call i32 @llvm.nacl.setjmp(i8* %env)
   ret i32 %i_other
 }
 ; Don't consider setjmp side-effect free, so it's not eliminated if
 ; result unused.
 ; CHECKO2REM-LABEL: test_setjmp_unused
 ; CHECKO2REM: call setjmp
 
+define float @test_sqrt_float(float %x, i32 %iptr) {
+entry:
+  %r = call float @llvm.sqrt.f32(float %x)
+  %r2 = call float @llvm.sqrt.f32(float %r)
+  %r3 = call float @llvm.sqrt.f32(float -0.0)
+  %r4 = fadd float %r2, %r3
+  br label %next
+
+next:
+  %__6 = inttoptr i32 %iptr to float*
+  %y = load float* %__6, align 4
+  %r5 = call float @llvm.sqrt.f32(float %y)
+  %r6 = fadd float %r4, %r5
+  ret float %r6
+}
+; CHECK-LABEL: test_sqrt_float
+; CHECK: sqrtss xmm{{.*}}
+; CHECK: sqrtss xmm{{.*}}
+; CHECK: sqrtss xmm{{.*}}, dword ptr
+; CHECK-LABEL: .L{{.*}}next
+; We could fold the load and the sqrt into one operation, but the
+; current folding only handles load + arithmetic op. The sqrt inst
+; is considered an intrinsic call and not an arithmetic op.
+; CHECK: sqrtss xmm{{.*}}
+
+define double @test_sqrt_double(double %x, i32 %iptr) {
+entry:
+  %r = call double @llvm.sqrt.f64(double %x)
+  %r2 = call double @llvm.sqrt.f64(double %r)
+  %r3 = call double @llvm.sqrt.f64(double -0.0)
+  %r4 = fadd double %r2, %r3
+  br label %next
+
+next:
+  %__6 = inttoptr i32 %iptr to double*
+  %y = load double* %__6, align 8
+  %r5 = call double @llvm.sqrt.f64(double %y)
+  %r6 = fadd double %r4, %r5
+  ret double %r6
+}
+; CHECK-LABEL: test_sqrt_double
+; CHECK: sqrtsd xmm{{.*}}
+; CHECK: sqrtsd xmm{{.*}}
+; CHECK: sqrtsd xmm{{.*}}, qword ptr
+; CHECK-LABEL: .L{{.*}}next
+; CHECK: sqrtsd xmm{{.*}}
+
+define float @test_sqrt_ignored(float %x, double %y) {
+entry:
+  %ignored1 = call float @llvm.sqrt.f32(float %x)
+  %ignored2 = call double @llvm.sqrt.f64(double %y)
+  ret float 0.0
+}
+; CHECKO2REM-LABEL: test_sqrt_ignored
+; CHECKO2REM-NOT: sqrtss
+; CHECKO2REM-NOT: sqrtsd
+
 define i32 @test_trap(i32 %br) {
 entry:
   %r1 = icmp eq i32 %br, 0
   br i1 %r1, label %Zero, label %NonZero
 Zero:
   call void @llvm.trap()
   unreachable
 NonZero:
   ret i32 1
 }
 ; CHECK-LABEL: test_trap
 ; CHECK: ud2
 
 ; ERRORS-NOT: ICE translation error
 ; DUMP-NOT: SZ