[PATCH v2 1/2] MIPS: math-emu: Update debugfs FP exception stats for certain instructions

[Aleksandar Markovic]

From: Aleksandar Markovic <aleksandar.markovic@xxxxxxxx>

Fix omission of updating of debugfs FP exception stats for
instructions <CLASS|MADDF|MSUBF|MAX|MIN|MAXA|MINA>.<D|S>.

CLASS.<D|S> instruction can generate "Unimplemented Operation"
FP exception. <MADDF|MSUBF>.<D|S> can generate "Inexact",
"Unimplemented Operation", "Invalid Operation", "Overflow",
and "Underflow" FP exceptions. <MAX|MIN|MAXA|MINA>.<D|S> can
generate "Unimplemented Operation" and "Invalid Operation" FP
exceptions. In all such cases (and prior to this patch),
SIGFPE signal was not generated, even though, according to
its specifications, it should be. Also, debugfs FP exception
stats were not updated, and therefore contained overall
wrong values.

This patch fixes those problems, and brings the emulation
of mentioned instructions consistent with the previously
implemented emulation of other related FPU instructions
(ADD, SUB, etc.).

Fixes: 38db37ba069f ("MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction")
Fixes: e24c3bec3e8e ("MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction")
Fixes: 83d43305a1df ("MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction")
Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Aleksandar Markovic <aleksandar.markovic@xxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # 4.3+
---
 arch/mips/math-emu/cp1emu.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index 16d9ef5..6f57212 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -1795,7 +1795,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			SPFROMREG(fd, MIPSInst_FD(ir));
 			rv.s = ieee754sp_maddf(fd, fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmsubf_op: {
@@ -1809,7 +1809,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			SPFROMREG(fd, MIPSInst_FD(ir));
 			rv.s = ieee754sp_msubf(fd, fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case frint_op: {
@@ -1834,7 +1834,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			rv.w = ieee754sp_2008class(fs);
 			rfmt = w_fmt;
-			break;
+			goto copcsr;
 		}
 
 		case fmin_op: {
@@ -1847,7 +1847,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(ft, MIPSInst_FT(ir));
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			rv.s = ieee754sp_fmin(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmina_op: {
@@ -1860,7 +1860,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(ft, MIPSInst_FT(ir));
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			rv.s = ieee754sp_fmina(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmax_op: {
@@ -1873,7 +1873,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(ft, MIPSInst_FT(ir));
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			rv.s = ieee754sp_fmax(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmaxa_op: {
@@ -1886,7 +1886,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			SPFROMREG(ft, MIPSInst_FT(ir));
 			SPFROMREG(fs, MIPSInst_FS(ir));
 			rv.s = ieee754sp_fmaxa(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fabs_op:
@@ -2165,7 +2165,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			DPFROMREG(fd, MIPSInst_FD(ir));
 			rv.d = ieee754dp_maddf(fd, fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmsubf_op: {
@@ -2179,7 +2179,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			DPFROMREG(fd, MIPSInst_FD(ir));
 			rv.d = ieee754dp_msubf(fd, fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case frint_op: {
@@ -2204,7 +2204,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			rv.l = ieee754dp_2008class(fs);
 			rfmt = l_fmt;
-			break;
+			goto copcsr;
 		}
 
 		case fmin_op: {
@@ -2217,7 +2217,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(ft, MIPSInst_FT(ir));
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			rv.d = ieee754dp_fmin(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmina_op: {
@@ -2230,7 +2230,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(ft, MIPSInst_FT(ir));
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			rv.d = ieee754dp_fmina(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmax_op: {
@@ -2243,7 +2243,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(ft, MIPSInst_FT(ir));
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			rv.d = ieee754dp_fmax(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fmaxa_op: {
@@ -2256,7 +2256,7 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			DPFROMREG(ft, MIPSInst_FT(ir));
 			DPFROMREG(fs, MIPSInst_FS(ir));
 			rv.d = ieee754dp_fmaxa(fs, ft);
-			break;
+			goto copcsr;
 		}
 
 		case fabs_op:
-- 
2.7.4